This is a rare Snap-on S-12 Swivel Grip Extension from the 1920s. It is a 10" extension with a 1/2in. drive size and is perfect for any automotive tool collector. The tool is made by Snap-on and comes with a manufacturer part number of SG-12. It includes one piece and is categorized under eBay Motors, Automotive Tools & Supplies, Hand Tools, and Sockets & Socket Sets.