balance screw holders Subgroups assortment nameopeninglengthcontentsitem No.balance screw holders0.30-0.50 mm100 mm3 pieces517370 separately nameopeninglengthcontentsitem No.balance screw holders0.30 mm100 mm1 piece517371balance screw holders0.40 mm100 mm1 piece517372balance screw holders0.50 mm100 mm1 piece517373