Roller stud extractor with 1/2" square drive. Beta 1433 1/2" Drive Roller Stud Socket Extractor/Inserter M8. For use with a 1/2" Drive ratchet or 21mm spanner on the external hexagon. The rollers are the concentric roller bearing type grip and can be used with any 1/2" Drive ratchets/bars etc and can also be used with a 21mm spanner where access is limited.
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