The "A" series consists of a body, ball and race. This type of construction allows for the use of different metals for each component part. The body is manufactured out of 4130 steel alloy, which is heat treated, and zinc plated. Specifications for the race are heat treated alloy steel, zinc plated, and chromate treated materials. The ball is made from 52100 steel (AMS-7440) and is heat treated and hard chrome plated.