MaterialThe impact socket set is made of Heavy-duty Chrome-Vanadium steel alloy (50BV30),durable and hard to use,a corrosion-resistant black phosphate finish.
seketman
SEKETMAN 3/8-Inch Drive Impact Socket Set,49 Pieces,SAE/Metric,Deep/Shallow,(5/16″-3/4″,8mm-22mm),6 Point,CR-V Steel,Includes Extension Bar,Adapter and Universal Joint
Material: 49 pieces impact socket set are made of chrome vanadium steel alloy (Cr-V),with a black phosphate protective coating,have good hardness and toughness.