General Tools 21 US Standard Sheet Metal Round Gage

General Tools US Standard Sheet Metal Round Gage (Model 21, Mfg Part 318-21) is a hardened, tempered alloy steel thickness gage designed to measure uncoated sheet metal, plate iron and steel. Gage numbers conform to U.S. Standard 0 to 36 (based on ounces per square inch); decimal equivalents for each size are stamped on the reverse. The gage features a satin/chrome finish, is 3-1/4" in diameter and 3/32" thick, and includes a single-piece round gauge for quick, accurate thickness checks. Made by General Tools, this gauge is hand-powered, includes one piece per package, and is suitable for industrial, shop, and field use where reliable sheet-metal thickness readings are required.

• Featuring a satin finished, this sheet metal gage is made from hardened and tempered heavy gage steel
• This standard sheet metal gage is 3-1/4" in diameter and 3/32" thick
• Decimal equivalents of each size are stamped on the reverse side of the sheet metal gage
• Gage numbers are US Standard 0 to 36, based on weights in ounces per square inch
• This sheet metal gage is designed to accurately determine the thickness of uncoated sheet metal, plate iron and steel