The Blue Spot 20 PCE 1/2" Deep & Shallow Metric Impact Sockets (10-19mm) are manufactured from heat-treated, tempered chrome molybdenum for strength & durability. ideal to be used with impact guns & high torque air tools. Deep & shallow impact socket for increased range & precision. Contents: 38mm length: 10, 11, 12, 13, 14, 15, 16, 17, 18, 19mm. 78mm length: 10, 11, 12, 13, 14, 15, 16, 17, 18, 19mm.