Board with the other half

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

STEP STL free, Xem Studio Design License — Xem Studio

Dimensions

dimension	key
value	40 long, 16 at the ends, 8 at the waist, 8 mm deep

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From the full sheet

Butterfly key (bow-tie, dutchman): every size, notes, mating features and sources. What size is a butterfly key?

Other sizes

Board with half the bow-tie socket
Bow-tie key, 8 mm deep
All parts in their assembled position (each part its own solid)