They provide excellent torque, whilst reducing the risk of rounding fasteners. 1 x 3/8in-1/2in Adaptor, 1 x 3/8in Hex Bit Adaptor. AB 36-38 & 55-56, BT (all), FK 17-21, HS (all), IM (all), IV (all), KA 27-28, KW (all), PA 20-99, PH 15-99, ZE (all), Channel Islands.
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