I lost one and couldn't find a 5/16" (or 8mm) replacement. It appears that 1/4" (6mm) quick release pins are much more common. I bought 2 packs to have spares in case I lose another one. They fit perfectly and should last forever if not lost.
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POWERTEC 4 Inch 20 2 Inch QTB1005 T Slot: A Revolutionary, High-Quality Power Tool Accessory!
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