... of washer High Quality Combination Screw 1. Head type of Combination Screw:ASTM/JIS pan head,hex head,.high round head, ... cheess head,flat head...ect..2. Drive of Combination Screw:Torx/6- ... and split washer with three washer4. Material of Combination Screw:Carbon steel, Alloy steel, stainless steel or according ... DIA 7mm 7mm 8mm 12mm 15mm High Quality Combination Screw