4pc Socket Stud Screw 1/2'' Drive Stud Extractor Socket Set 6,8,10,12MM Hex Ends

It can also be used with 21mm spanners with the hex drives on the top of the socket. Hex ends allow use with 21mm spanner. 1/2" Drive 21mm Spanner or Ratchet 6mm, 8mm, 10mm and 12mm. Integrated concentric roller bearings stud extractors.