SAE sizes. 3/8-3/4 flex ratcheting box end and open end combination wrench 7 piece set. Ratcheting box-end needs as little as 5 degrees to move a fastener. Has an adjustable set screw, for desired head tension, The flex head tilts up to 180 at any interval. Mirror chrome finish and all metal construction for long-lasting durability. Set Includes: 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, and 3/4. Convenient plastic caddy for storage.