This is Craftsman 1/4" 3/8" 1/2" 3/4" Drive Socket Adapter Set - 5 pcs. 3/8" x 1/4" Adapter - Part # 4256. 1/4" x 3/8" Adapter - Part # 4257. 3/8" x 1/2" Adapter - Part # 4258. 1/2" x 3/8" Adapter - Part # 4259.
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