... Wafer Head Self Tapping Screw with Very Long Length Head type: CSK/flat head, truss head, trumpet head, wafer head ... head, pan wafer head, hexagon head, pan headThread type: type A, type B, type C, hi-low, double thread and other special threadLength ... phosphated, black zinc, black oxide, dacrotized, ruspert, xylanPacking: in bulk, standard packing for exportThey have good quality, and reasonable price ...