3/8" - 10mm, 11mm, 12mm. 1/2" - 13mm, 14mm, 16mm, 17mm. Designed for the safe removal of bolts that have rounded off, rusted or painted over. Suitable for hand and power tools. Can be used with 3/8" breaker bar/ratchet and also has flats so that they can be used with spanners or wrenches.
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