Pin Keeper Size: 1.9x6x5mm(0.07x0.24x0.2)(Inner Dia Outer Dia H), suitable size for holding lost pins firmly! Pin Keeper Size: 1.9x6x5mm(0.07x0.24x0.2)(Inner Dia Outer Dia H). Material: The locking pin backs are made of plated copper, rendering them rustproof, and durable, without worrying they will fall off.
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