This J-Cobs Piston Dock is made from a 1940's radial engine piston called the WWII Jacobs R-755. The piston was used to power such airplanes as the Beechcraft Staggerwing, Boeing Stearman 75, and Avro Anson. The piston has been buffed to a mirror-like luster and measures 5" in diameter and 3" in height. The piston dock is designed to fit an iPhone, iTouch, or iPod that uses the Apple 30-pin connector. A Plane Pieces Inc. original design, this piston dock is made in the USA. The 250-piece limited edition features hand-engraved numbering at the bottom of the charging dock. The dock comes with a 6-foot black USB cord and wall charger. The charger is designed to perfectly fit your iPhone, iTouch, or iPod without a protective case. It may not work correctly if you are using certain protective cases.