Library › Hardware › Hex bit shank 1/4 in (ISO 1173 C 6.3 and E 6.3): across flats 6.35…

hex pocket gauge plate, 86.6 × 28.7 × 12 mm

hex pocket gauge plate, 86.6 × 28.7 × 12 mm: five through hexagon holes at the ISO 1173 s max across flats 3.96, 6.35 (1/4 in), 7.93, 11.11 and 12.70 mm, smallest first, 6 mm between the holes' across-corners extents; plate size, thickness and corner radius are Xem choices; hole sizes are the shank's own maximum, so add your process allowance to them

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

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From the full sheet

Hex bit shank 1/4 in (ISO 1173 C 6.3 and E 6.3): across flats 6.35 mm, across corners 7.18 mm, form C and E dimensions, 4–12.5 mm sizes + hex pocket gauge: every size, notes, mating features and sources. What are the dimensions of a 1/4 inch hex bit shank (C 6.3 / E 6.3), and what size hex pocket does a bit holder need?