The Snap-on 3/8" Drive 6-Point Swivel Ball Extension Sockets, No. PFSXM910B, 911B, 912B, 913B, 914B and 915B, allow for the use of only one tool instead of three different ones to get at areas on a vehicle where a socket and extension will not fit. Nine-inches in length, the Swivel Ball Extension Sockets are ideal for removing and installing transmission bolts and starter bolts. Available in six sizes: 10mm (PFSXM910B), 11mm (PFSXM911B), 12mm (PFSXM912B), 13mm (PFSXM913B), 14mm (PFSXM913B) and 15mm (PFSXM915B), the swivel ball extension sockets can be used on most domestic, Asian and European vehicles.