Socket inserts E-profile, drive inner square 12.5mm (1/2"): E18.E20.E22.E24. 10mm(3/8"): E10 -E11, E12, E14, E16. 6.35mm(1/4"): E4 -E5, E6, E7, E8. 14x socket insert. Practical socket wrench set 1/2" and 1/4"and 3/8", without unnecessary filling sizes for professional users.
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