Wera 05003590001 8784 b1 zyklop adaptor 3 8in drive wera 05003590001 this zyklop adaptor from wera is made from chrome vanadium and has a quick release chuck for fast bit changes it has a 3 8in square drive and is suitable for use with 1 4in hex bits wera 05003590001 8784 b1 zyklop adaptor 3 8in drive