TEKTON 4971 1/2-Inch Drive Impact Extension Bar Set, Cr-V, 3-Piece N/A Made in USA or Imported Engineered for use with impact drivers Adds length to access hard-to-reach fasteners Spring-loaded detent balls securely latch onto sockets, preventing them from being dropped Through-hole in drive ends locks onto drive tang Made of premium chrome vanadium steel with a protective black oxide finish