1 x stud extractor - 6mm - 3/8" drive. 1 x stud extractor - 8mm - 3/8" drive. 1 x stud extractor - 10mm - 1/2" drive. 6mm (1/4"), 8mm (5/16"), 10mm (3/8") and 12mm (1/2"). The rollers are the concentric roller bearing type grip.
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