Bit Adapter Socket for 5/16" Driver Bits - Fits 3/8"-Drive Ratchet Handles Ingenious adapter socket lets you use any 5/16" shank driver bit with 3/8"-drive socket ratchet handles, breaker bars or air wrenches Heavy-duty chrome-vanadium steel alloy for high-torque applications Pre-drilled hole on ratchet end fits over anvils with ball bearing for extra hold. Ball bearing on bit end keeps bits from falling out Works with all 5/16" hex-shank flat/slotted, phillips, star, TORX, tamper-proof and other style bits Excellent quality - made in Taiwan