Measuring 2-3.5 in. long, Stanley-Proto Deep Thin Wall impact sockets are available in metric sizes for 3/8 in. drives and are suited for hard-to-reach fasteners that require low impact force. Each has Stanley-Proto TorquePlus design in which socket's curved points contact fastener away from corners, and spread force of turning over larger area of fastener. All include one through-hole and groove to accept retaining ring along with pin to secure socket to power tool anvil.