Skip to content

Lines & plumb bobs

General Tools Hexagonal steel plumb bob, 8 oz, GGG-P-501e

The only plumb bob on this shelf measured against a published specification — and the cheapest bob on it.

General Tools hexagonal nickel-plated steel plumb bob

General Tools Hexagonal steel plumb bob, 8 oz, GGG-P-501e

The only plumb bob on this shelf measured against a published specification — and the cheapest bob on it.

Also stated
Conforms to government specification GGG-P-501e, stated — the US federal specification for plumb bobs, which fixes the form, the weight tolerance and the finish. It is the ONLY standard cited anywhere on this shelf and the only one in the American chantier for this site: every other bob here is sold on its material and its weight, with nothing against which either is checked
Stated dimension or range
8 oz, 4 inches long and 7/8 inches wide — the only bob DIMENSIONS published on this shelf. Length and width matter on a bob: a long thin bob hangs closer to a wall before it fouls, and a short wide one has more surface for a draft to push
Material
A hexagonal body of COLD-DRAWN steel, nickel plated to prevent rust. Cold-drawn rather than cast or turned from bar: the grain runs along the body, which is why a cold-drawn bob survives being dropped on its side. Hexagonal, stated, which also means it will not roll off a board
Body and fittings
A removable cord cap for easy cord replacement, sized for 3/32 inch cords. A named cord size is unusually practical: it means a replacement can be bought by specification rather than by trying it
Supplied
A 10-foot 3 mm (0.12 in) BRAIDED cord and the removable cap. Ten feet is the shortest line on this shelf — the retracting reels carry 14 and 14.5 feet and the mason's line reel carries 250 — but it is braided, which this shelf's introduction says resists the stretch that makes a twisted line sag differently at each setting
Measuring mode
No settling time is published, and this shelf's introduction says weight sets how quickly a bob settles. Eight ounces is the middle-light end of this shelf, which runs 5 to 21 oz; one maker here publishes six seconds for a ten-ounce bob
Amazon reference
B00004T7TI
EAN
0038728426154
  • The only published standard on this shelf: GGG-P-501e
  • The only published bob dimensions: 4 in by 7/8 in
  • Ten feet of cord, the shortest line here

Best for: A bob that has to be the right shape and weight, bought once and kept in a toolbox

≈ $7
Check price on Amazon

Specifications

Also stated
Conforms to government specification GGG-P-501e, stated — the US federal specification for plumb bobs, which fixes the form, the weight tolerance and the finish. It is the ONLY standard cited anywhere on this shelf and the only one in the American chantier for this site: every other bob here is sold on its material and its weight, with nothing against which either is checked
Stated dimension or range
8 oz, 4 inches long and 7/8 inches wide — the only bob DIMENSIONS published on this shelf. Length and width matter on a bob: a long thin bob hangs closer to a wall before it fouls, and a short wide one has more surface for a draft to push
Material
A hexagonal body of COLD-DRAWN steel, nickel plated to prevent rust. Cold-drawn rather than cast or turned from bar: the grain runs along the body, which is why a cold-drawn bob survives being dropped on its side. Hexagonal, stated, which also means it will not roll off a board
Body and fittings
A removable cord cap for easy cord replacement, sized for 3/32 inch cords. A named cord size is unusually practical: it means a replacement can be bought by specification rather than by trying it
Supplied
A 10-foot 3 mm (0.12 in) BRAIDED cord and the removable cap. Ten feet is the shortest line on this shelf — the retracting reels carry 14 and 14.5 feet and the mason's line reel carries 250 — but it is braided, which this shelf's introduction says resists the stretch that makes a twisted line sag differently at each setting
Measuring mode
No settling time is published, and this shelf's introduction says weight sets how quickly a bob settles. Eight ounces is the middle-light end of this shelf, which runs 5 to 21 oz; one maker here publishes six seconds for a ten-ounce bob
Amazon reference
B00004T7TI
EAN
0038728426154

What the maker puts in writing

  • “It conforms to government specifications GGG-P-501e”
  • 8 oz, 4 inches long, 7/8 inches wide
  • Hexagonal body of cold-drawn steel, nickel plated to prevent rust
  • Removable cord cap for easy cord replacement; cap is used with 3/32 inch cords
  • Includes a 10 foot long 3 mm (0.12 in) braided cord
  • A staple of the masonry, carpentry and surveying industries for more than 50 years

No settling time. No replaceable tip. No reel.

A specification, which nothing else here has

GGG-P-501e. The US federal specification for plumb bobs.

A federal specification fixes what the thing HAS to be: the form of the body, the tolerance on the stated weight, the tip geometry, the finish.

So a bob built to it is a known quantity rather than a shape somebody liked.

Every other bob on this shelf is sold on its material and its weight, with nothing to check either against.

On a seven-dollar tool that is the whole argument.

Four inches by seven-eighths

The only bob dimensions on this shelf, and both are useful.

LENGTH decides how close to a wall, a post or a jamb the bob can hang before the body touches and the reading is lost. A short fat bob of the same weight fouls sooner.

WIDTH decides how much air a draft has to push. This shelf’s introduction says a heavy bob swings less in a draft — a slim one swings less for the same weight.

Cold-drawn, which is about being dropped

Not about rust.

Cold drawing runs the grain along the body. A cold-drawn bob survives landing on its side where a casting cracks.

The nickel plating is the rust part, and it is a skin: a chipped plated bob has a rust seed in the chip. The brass bobs on this shelf have no skin to chip.

And hexagonal, so it stays on the board

The same reason a carpenter’s pencil is flat.

Two bobs on this shelf are hexagonal and both say why.

Ten feet is one story

Ceiling to floor in an ordinary room, with a little spare.

Not a stairwell, not a lift shaft, not two lifts of scaffold — and the retracting reels here carry 14 and 14.5 feet.

The cord is 3 mm (0.12 in) braided and the cap is removable and specified for 3/32 inch. So a longer cord is a specified replacement rather than a bodge.

Availability

On sale at around 7 € on the American Amazon store at the time of checking.

Prices and availability are what Keepa reported on the date this page was updated; both move.

Prices quoted in this text were read on 8 October 2026. The live price is at the top of the page.

What gets asked here

What is GGG-P-501e?

The United States federal specification for plumb bobs, and the only standard cited anywhere on this shelf. A federal specification fixes what the thing has to be: the form of the body, the tolerance on the stated weight, the tip geometry and the finish — so a bob built to it is a known quantity rather than a shape somebody liked. That is unusual on a consumer listing and it is the reason to prefer this bob over an unspecified one at the same price: every other bob here is sold on its material and its weight, with nothing to check either against.

Why do the dimensions matter?

Because a bob hangs next to something. Four inches long and seven-eighths of an inch wide describes a slim bob, which can be dropped close to a wall, a post or a door jamb before the body touches and the reading is lost — a short fat bob of the same weight fouls sooner. The width also sets how much air a draft has to push against, and this shelf's introduction says a heavy bob swings less in a draft; a slim one swings less for the same weight. No other bob on this shelf publishes either figure.

Is ten feet of cord enough?

For a story, and not for much more. Ten feet reaches from a ceiling to a floor in an ordinary room with a little spare, which is most interior plumbing of a wall or a door frame. It will not drop down a stairwell, a lift shaft or two stories of scaffold — and the retracting reels on this shelf carry 14 and 14.5 feet for exactly that. The cord is 3 mm (0.12 in) braided and the cap is removable and sized for 3/32 inch, so a longer cord is a cheap and specified replacement rather than a bodge.

More mason lines and plumb bobs

  • HCCMLOVE eight-ounce steel plumb bob with line board and pencils

    HCCMLOVE Plumb bob set, 8 oz, 16 ft braided line

    Sixteen feet of braided line, which is more than any other bob here carries — wound on a card rather than a reel.

    Stated dimension or range
    8 oz / 227 g, with 16 FT (5 m (16 ft)) of nylon braided line. Sixteen feet is the longest bob line on this shelf — the retracting reels carry 14 and 14.5 ft and a steel bob ships 10 ft — and on a stairwell or a two-story drop that difference is the whole job
    Material
    High-quality steel, stated corrosion-resistant, with a sharp point for calibration. NYLON BRAIDED line, stated — which this shelf's introduction says resists the stretch that makes a twisted line sag differently at each setting
    Functions
    A FAST Stabilizing DEVICE at the end of the bob, stated to speed up the stabilization of the line. No time is given — the Tajima bobs on this shelf publish six seconds — but the feature is the same idea: this shelf's introduction says weight sets how quickly a bob settles, and a damping device is the other way to get there without adding mass
    Body and fittings
    A safety cap over the point, stated to make it safer to use, and an anti-slip band at the waist of the bob to prevent it slipping off the line. The cap is the same answer to the same problem as the elastomer tip guard on another bob here: the point is what a plumb bob dies of
    Supplied
    The bob, a line board holding the 16 ft of braided line, TWO pencils and a sharpener. The line board is a card rather than a reel: the line is unwound by hand and rewound by hand, and the board can be held or weighted down to fix the top of the line, which is how HCCMLOVE describes using it
    Reference and mounting
    Nylon clips to adjust the line length for different heights, stated. No magnet, no pin and no hook: the top of the line is fixed by holding the board or weighting it, which is the simplest arrangement on this shelf and the least secure
    Amazon reference
    B0C86R3MNR
    EAN
    0765365646538
    • Sixteen feet of line, the longest bob cord on this shelf
    • Braided nylon, which resists stretch
    • A line board, not a reel: wound and unwound by hand

    Best for: A tall drop on a budget, where sixteen feet of line matters more than a reel to wind it on

    ≈ $15
    Check price on Amazon
  • Johnson five-ounce hexagonal machined steel plumb bob

    Johnson Hexagonal steel plumb bob, 5 oz

    The lightest bob here, and the only one sold for the job a surveyor actually keeps one for: centering a tripod.

    Stated dimension or range
    5 oz — the lightest bob on this shelf, where the heaviest is 21 oz. Light is the right choice for a tripod hook, where the bob hangs a few inches and settles in a moment; this shelf's introduction says a heavy bob steadies faster and swings less in a draft, and both of those matter on a long drop rather than a short one
    Functions
    Stated to be used with JOHNSON TRIPODS to center them while using optical and laser instruments. It is the only bob on this shelf sold for that job, and it is the job a surveyor keeps a bob for: an instrument reads angles from wherever its tripod actually stands, so a theodolite or a level over a station mark has to be positioned by dropping a point from its own center
    Material
    A hexagonal MACHINED steel body with a corrosion-resistant plated finish, stated. Machined rather than cold-drawn — which is the other bob on this shelf — means turned to shape, so the concentricity of the point to the body is a machining tolerance rather than a drawing one
    Body and fittings
    A hexagonal body stated to prevent it rolling off, and a removable cap stated to allow quick, easy and accurate Centered string installation. Centered is the operative word: a bob whose string is not on the axis hangs at a slight angle and its point lands beside the truth
    Supplied
    The bob. No line, no reel and no case — so the string is bought separately, and the cap is what makes that a specified job rather than a knot round a hook
    Also stated
    Named for foundation contractors, excavation contractors and surveyors, for lining up and transferring points. No settling time, no dimensions, no tip guard and no spare tip is published
    Amazon reference
    B00002N7U8
    EAN
    0049448050000
    • Five ounces, which is right for a tripod hook
    • The only bob here stated for centering a tripod
    • No line supplied at all

    Best for: Centering a tripod over a station mark, and transferring points indoors

    ≈ $9
    Check price on Amazon
  • kwb red braided mason line wound on its card

    kwb Braided mason line, 50 m (164 ft) × 1.2 mm (0.05 in)

    The only line here that publishes its strength: 22 decanewtons breaking, about 4.75 kg (10.5 lb) continuous — the figures that decide how hard it can be tensioned.

    Amazon reference
    B00TEAM5TG (identical on 6 markets)
    EAN
    4009319251253
    Stated dimension or range
    50 m (164 ft) × 1.2 mm (0.05 in)
    Mechanism and finish
    braided nylon
    Stated tension
    22 daN
    Stated weight
    ~4.75 kg (10.5 lb) working load
    • Publishes both a breaking load (22 daN) and a continuous working load (about 4.75 kg (10.5 lb))
    • Braided rather than twisted, which resists the stretch that makes a line sag differently at each setting
    • Line only — no plumb bob

    Best for: Setting out brickwork, paving and tiling, where the line is tensioned between two points and has to stay straight.

    Check price on Amazon

Elsewhere in the spares drawer

  • PeakTech P 7610 high-voltage instrument fuse alongside a multimeter

    PeakTech Fast-acting fuse, 0.5 A, 6.3 × 32 mm (0.25 × 1.26 in)

    The instrument-grade format: 6.3 × 32 mm (0.25 × 1.26 in) at a rated 690 V, super fast-acting, which is what a properly specified meter current input takes.

    Amazon reference
    B07SQQXXP3 (identical on 5 markets)
    EAN
    4250569402852
    Stated dimension or range
    6.3 × 32 mm (0.25 × 1.26 in)
    Fuse rating
    500 mA · 690 V rated · super fast-acting (FF)
    • A 690 V rating, far above the 250 V of the general-purpose fuses here
    • The 6.3 × 32 mm (0.25 × 1.26 in) format used by instrument current inputs
    • One value only — 500 mA, which fits the low current range and not the 10 A input

    Best for: The meter whose manual specifies exactly this — and it should be checked, not assumed.

    Search Amazon for this model
  • SeKi ceramic 5 by 20 millimeter fuses in a row on a workbench

    SeKi Ceramic fuses, 10 A, 5 × 20 mm (0.20 × 0.79 in), ten-pack

    Ten ceramic fuses with all four specifications stated — size, current, voltage and characteristic — which is the only way a replacement fuse can be chosen.

    Amazon reference
    B0CVXQGP7P (identical on 5 markets)
    EAN
    4053171962161
    Stated dimension or range
    5 × 20 mm (0.20 × 0.79 in) ceramic
    Fuse rating
    10 A / 250 V · time-delay (T)
    • All four figures published: 5 × 20 mm (0.20 × 0.79 in), 10 A, 250 V, time-delay
    • Ceramic bodies, which is what a meter's current input normally specifies
    • A 250 V rating is below what many meters specify for the current input

    Best for: The meter whose manual specifies exactly 5 × 20 mm (0.20 × 0.79 in), 10 A, 250 V, time-delay — and no other.

    Search Amazon for this model
  • YUNFOOK DMM-11A multimeter fuses, two in a pack

    YUNFOOK Fast-acting fuse, 11 A, 10 × 38 mm (0.39 × 1.50 in), pair

    The cheapest 1000 V fuse per piece on this shelf, and the only one that names the part number it replaces.

    Stated dimension or range
    10 mm (0.39 in) × 38 mm (1.50 in), stated, and then repeated in inches as 0.41" × 1.50". That is the high-energy instrument format, the same as the Klein on this shelf — and more than the Fluke page gives, which publishes no fuse dimensions at all
    Current rating
    11 A, stated, matching the Fluke and differing from the Klein's 10 A. The listing adds a sentence the other two do not: "Always verify these specifications match your meter's original fuse before installation. Using an incorrect fuse can be a serious safety hazard" — which is this shelf's buying tip, written by the seller
    Voltage rating
    1000 V AC and DC, stated. Both polarities named, which the other two leave implicit. No fuse previously published on this shelf is rated above 690 V
    Breaking characteristic
    Fast-acting, stated, with the reason given: "rapid protection for your meter's sensitive internal circuitry (and for you) in case of accidental overload". No breaking capacity in kiloamps is published
    Body type
    NOT PUBLISHED. Five long bullets and a page of prose, and nowhere does it say ceramic or glass. The shelf's tag line is that a glass fuse in a meter specifying ceramic is not a substitute, and this is a 1000 V part — which is precisely where the distinction bites
    Supplied
    TWO fuses, $11.69, so $5.85 each — the cheapest 1000 V piece on this shelf. The Fluke five-pack is $8.48 each and the single Klein is $15.99. For a drawer that wants one spare rather than four, a pair is the sensible quantity
    Also stated
    A direct replacement for multimeter fuse part number 803293, and stated to suit meters from Fluke, Amprobe, BK Precision and Klein Tools that specify an 11 A / 1000 V fuse, with "check your meter's manual to confirm". It is the only fuse on this shelf that names the part number it stands in for, and it names BRANDS rather than models
    Amazon reference
    B0G8WXL5S7
    EAN
    0716841567298
    • Five eighty-five a fuse, the cheapest 1000 V part here
    • Dimensions in millimeters and in inches
    • No body material: ceramic or glass is never said

    Best for: Keeping spares for an 11 A / 1000 V current input, where the manual gives a part number rather than a brand

    ≈ $12
    Check price on Amazon

All mason lines and plumb bobs