The Monster 12-pc Spline T- handle Extended Universal Socket Set, No. MST9112, made of chrome vanadium, includes the common metric sizes and a “T” bar. The 3/8” universal joint long sockets are designed with a super thin extension, according to the company. The MST9112 includes a lifetime warranty and the following sizes of Universal Joint Long Sockets: 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm and 19mm.