Size charts · Bolting
Bolting sizes.
Hex head fasteners, metric and imperial. Pick a diameter and a length and see it drawn to scale, with the across flats, head height and pitch — and the thread length, which is the figure that decides whether the plain shank lands in your clearance hole.
SZ-01 / DWS·DAVENTRY
Hex setscrew sizes
Fully threaded, DIN 933 and ISO 4017. Pick a diameter and length and get the across flats, head height and pitch, with the fastener drawn to size in your choice of finish.
M1.6 – M64 · DIN 933 · ISO 4017 · Six finishes
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SZ-02 / DWS·DAVENTRY
Hex bolt sizes
Part threaded with a plain shank, DIN 931 and ISO 4014. Same picker, plus the threaded length for every size — the figure that decides whether the shank lands in your clearance hole.
M1.6 – M64 · DIN 931 · ISO 4014 · Thread length
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SZ-10 / DWS·DAVENTRY
UNC & UNF hex set screw sizes
Imperial hex, threaded full length, 1/4 to 1 inch. The AF spanner size and head height — and the coarse or fine thread, which the diameter alone will not tell you.
1/4" – 1" · ASME B18.2.1 · UNC / UNF · BZP / self-colour
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SZ-12 / DWS·DAVENTRY
UNC & UNF hex bolt sizes
The imperial hex with a plain shank, 1/4 to 1 inch. Spanner size, head height and how much of it is thread — 2D plus a quarter inch, by the standard's own rule.
1/4" – 1" · ASME B18.2.1 / BS 1768 · UNC / UNF
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Setscrew or bolt?
A setscrew is threaded all the way to the head. A bolt has a smooth plain shank under the head with the thread only on the far part of the shaft. Same hexagon, same spanner, different fastener — and the reason the trade keeps them separate is the shank: it takes the shear where the joint moves, and it has to be long enough to fill the clearance hole.
If the plain shank ends inside the threads of the part you are bolting into, the joint is carrying load on thread instead of shank. That is the figure the bolt chart prints for every size.
Not sure which you need?
Bring the old one in, or send us a photo. We are on Baird Close in Daventry with metric and imperial stock across the common classes and finishes.
More size charts
Every size, drawn to scale.
Hex setscrews
DIN 933 · full thread
Hex bolts
DIN 931 · part thread
Socket cap screws
DIN 912
Low head cap screws
DIN 7984
Button head screws
ISO 7380-1
Flanged button heads
ISO 7380-2
Countersunk socket screws
DIN 7991
Grub screws
DIN 913–916 · five points
Nuts
DIN 934 · nyloc · thin · Stover · flange
Washers
ISO 7089 · BS 4320 · penny
Not sure what the markings on the head mean? Bolt grades explained covers 8.8, 10.9, 12.9, stainless A2 and A4, and the imperial SAE grades.
All of it comes off the shelf at Baird Close — see the full fasteners & fixings range, or every size guide.