Ratchet action open end wrench; the member providing the ratchet action displaces to allow the wrench to slip onto a nut. Alternate mechanisms are shown in the drawings and described in the specifications. The BRILES MFG. PAWLOCK uses the least complicated of those mechanisms.
The specifications note U.S. patent nos. 1,512,180, 2,697,372, and 2,592,781, and German patent no. 220,348.
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