TEKTON 1660 9-pc. Combination Wobble Extension Bar Set Selling Unit: Set Features: Drop forged, heat treated chrome vanadium steel Corrosion-resistant chrome plated finish Knurled-pattern grip area for sure, non-slip handling Spring-loaded ball bearing retains socket Unique, combination design fits into socket in two positions: fully inserted for standard extension or partially inserted for wobble extension, providing offset clearance for hard-to-reach fasteners