Socket head cap screws, inch: #10-24, #10-32, 5/16-18, 3/8-16, 1/2-13 (ASME B18.3) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/socket-head-cap-screws-inch/  (CC BY 4.0)
Basis: ASME B18.3 inch socket screws: head diameter A (max), head height H, hex socket J; thread drawn as a plain cylinder at the major diameter
Catalog version: 2026-10-20

Sizes: see table below
- The inch sizes above 1/4-20 (the #4 to 1/4-20 sizes are on the imperial machine screws page). 5/16-18 is the screw for 15-series (1.5 in) T-slot brackets, gussets and slide-in T-nuts; 1/4-20 for 10-series.
- Length is under the head. Threads are plain cylinders at the major diameter.

size  major_mm  tpi  head_dia_mm  head_h_mm  hex_key_in  lengths_in
#10-24  4.826  24  7.92  4.83  5/32  0.375, 0.5, 0.625, 0.75, 1
#10-32  4.826  32  7.92  4.83  5/32  0.375, 0.5, 0.75, 1
5/16-18  7.938  18  11.91  7.94  1/4  0.5, 0.625, 0.75, 1, 1.25, 1.5, 2
3/8-16  9.525  16  14.27  9.52  5/16  0.75, 1, 1.25, 1.5, 2
1/2-13  12.7  13  19.05  12.7  3/8  1, 1.5, 2, 2.5

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- ASME: B18.3 Socket cap, shoulder, set screws, hex and spline keys (inch series): head diameter, height, hex socket — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/b18-3-socket-cap-shoulder-set-screws-hex-spline-keys-inch-series

Free files (CC BY 4.0, Xem Studio; STEP + STL, 25 parts): https://xemstudio.com/files/hardware/socket-head-cap-screws-inch/index.json
API: https://xemstudio.com/api/geometry?object=socket-head-cap-screws-inch