Knurled ring for extra grip with oily fingers. Supplied with socket rail. Model No AK2671. Type: 1/4″Sq Drive – Imperial. Contents: 5/32″, 3/16″, 7/32″, 1/4″, 9/32″, 5/16″, 11/32″, 3/8″, 7/16″, 1/2″, 9/16″, Socket Rail.