The Wahlstrom Tool Co. manufactured Verner J. Wahlstrom's drill chuck that was patented in 1912. Over a century later this drill chuck is still in production. We have seen examples explicitly labeled as a Wahlstrom chuck and made by Wahlstrom Tool Co., by American Machine & Foundry Co. (AMF), and by Wahlstrom Float-Lock Product Co. (of LIbertyville, IL).