The Park Tool CTP-4K Chain Pin Replacement Kit includes four (4) replacement chain tool pins and one 5/32" ball bearing. To replace the chain tool pin, unscrew the cap, and pull out the old pin. Use care not to lose the ball bearing beneath the pin. Install the new pin and replace the cap. Replacement part for Park Chain Tool: CT-4, CT-4.2, CT-4.3, CT-11.