The SK Hand Tool 12-pc Spark Plug Socket Set features 12 different sizes and styles of spark plug sockets to fit a variety of vehicles. Each socket has the SuperKrome finish that results in a jewelry-like finish and provides maximum corrosion resistance. Each socket also has a durable rubber retainer that holds spark plugs securely during installation and removal. The universal 12-piece set contains flex and non-flex sockets, along with extra deep sockets in metric and fractional. The sockets are made in the U.S.A. with American steel and come with a lifetime warranty.