29支套高速钢麻花钻阶梯盒/29PCS TWIST DRILL SET WITH PLASTIC STEP BOX H2901-1 BLACK FINISHED H2901-2 EDGE GROUND H2901-3 EDGE GROUND TIN COATED H2901-4 FULLY GROUND BRIGHT H2901-5 FULLY GROUND BLACK FINISHED H2901-6 FULLY GROUND TIN COATED SIZE(MM):1/16-1/2X1/64