3/8"drive so will fit any 3/8" drive ratchet / bar etc. 140mm total length of the allen key without the socket. US PRO INDUSTRIAL 3/4" DR Extendable Ratchet 630mm to 1000mm 4168. Hobby Tools. US PRO INDUSTRIAL 1/2" Dr 72T Tooth Extra Long Curved 380mm Ratchet Handle 4212.
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