Rust Resistant 6pcs Socket Convertor Adaptor Set Ball Bearing Fixation

Adopting a four-corner square head design, this sleeve converter kit has a ball bearing to for ensure a firm fixation. Size:3/8 hole 1/4 head. 1/4 hole 3/8 head. 1/2 hole 3/4 head(as picture ). 3/8 hole 1/2 head.

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