Square drive sizes ISO 1174: 1/4, 3/8, 1/2, 3/4, 1 in drive (6.3, 10, 12.5, 20, 25 mm): male and female square limits + stub rail and pocket plate — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/square-drive-iso-1174-1-4-to-1-in/ (sheet CC BY 4.0) Basis: ISO 1174-1:1996 free sample (male squares types A and B, female squares types C and D, separation force); two Xem-drawn example plates for rack and holder design Catalog version: 2026-10-20 Overall (mm): length 121.0, width 41.4, height 18.0 - The square drive on ratchets, extensions and sockets is ISO 1174-1: nominal sizes 6.3, 10, 12.5, 20 and 25 mm, which are the 1/4, 3/8, 1/2, 3/4 and 1 in drives. The male square s1 is 6.35 / 9.53 / 12.70 / 19.05 / 25.40 mm at its maximum (the inch fractions to the hundredth) with the minimum 0.09 to 0.13 mm lower. The female square s2 limits (the hole in the socket) are above the male: 6.63 / 6.41, 9.80 / 9.58, 13.03 / 12.76, 19.44 / 19.11, 25.79 / 25.46 mm (max / min). The minimum separation force of the retaining detent is 4, 11, 25 and 45 N for 6.3, 10, 12.5 and 20 mm (no 25 mm value was readable). - The standard's free sample prints other columns (the corner dimensions e1 and e2, the retaining hole d2, depths l2 and l3, corner radii r1 and r2), but the OCR of this sample is partly garbled and those columns could not be assigned to sizes with confidence, so they are not listed. The detent ball size and the retaining-hole position are not specified in the sample (the text only says a female square with a retaining hole, not a recess, is used with a plunger retainer), so no detent ball diameter is given: measure the ball on the tool you design to. McMaster-Carr and other catalogues list drive sizes only. - Tool-holder use: a rack that holds sockets by the square needs a male stub of s1 max or slightly under (a socket's female square is s2 min or larger, and must slide over the post); a handle or adapter with a female square needs a hole of at least s2 min. The two plates are Xem examples drawn at true size: the stub rail posts at s1 max, the pocket plate holes at s2 min. For sockets that must grip, use the standard's separation force and your own detent. - Not here: socket bodies and wall thickness (ASME B107.1), impact-socket squares and their pin holes (ISO 2725 / ASME B107.4 are separate standards), ratchet head sizes, spline and wobble drives, and 1-1/2 in and larger squares. nominal (mm) drive (in) male s1 max (mm) male s1 min (mm) female s2 max (mm) female s2 min (mm) min separation force (N) 6.3 1/4 6.35 6.26 6.63 6.41 4 10 3/8 9.53 9.44 9.80 9.58 11 12.5 1/2 12.70 12.59 13.03 12.76 25 20 3/4 19.05 18.92 19.44 19.11 45 25 1 25.40 25.27 25.79 25.46 — Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - ISO (iTeh Standards free sample): ISO 1174-1:1996 square drive: male squares (types A, B) and female squares (types C, D), 6.3 to 25 mm, separation force — web — Standards body sample pages; dimensions are facts — https://cdn.standards.iteh.ai/samples/23590/fd20f8b72777452ba01817d07f90c2e8/ISO-1174-1-1996.pdf Free files (CC BY 4.0, Xem Studio; STEP + STL, 2 parts): https://xemstudio.com/files/hardware/square-drive-iso-1174-1-4-to-1-in/index.json API: https://xemstudio.com/api/geometry?object=square-drive-iso-1174-1-4-to-1-in