This 3/8-Inch drive, 16-Piece SAE and METRIC set is forged from the finest Molybdenum alloy steel-the best choice for strength and durability. Features a radius corner design causing the socket to grab the sturdy wall, or flat, of the fastener instead of grabbing the corners. This results in less corner wear on the fastener. Set Includes SAE sizes: 1/4-Inch, 5/16-Inch, 3/8-Inch, 7/16-Inch, 1/2-Inch, 9/16-Inch, 5/8-Inch and 3/4-Inch and Metric sizes: 6mm, 7mm, 8mm, 10mm, 12mm, 14mm, 17mm, 19mm.