Material: Chrome Vanadium Steel Drive size (in.) 1/4 in., 3/8 in., 1/2 in. Triple chrome plated High visibility markings for easier, faster socket selection 9 Piece Set This wobble extension set is designed to “wobble” when in contact with the socket providing enough flex to get a firm grip. Constructed from resilient chrome vanadium, each socket features high visibility markings for quick socket selection. The wobble extension set is ideal for auto shops, garages and for any project with hard-to-reach nuts and bolts!