M2 M3 M4 M5-M44.5 Delrin Polyoxymethylene ( Pom ) Solid Plastic Bearing Balls Size:2-44.5mm Material: Plastic Pom Manufactured from Polyoxymethylene ( Pom ), Also Known As Acetal, Polyacetal & Polyformaldehyde. Commonly Known As Delrin, Celcon, Hostaform, Duracon, Kepital, Lupital & Ultraform High Mechanical Strength and Rigidity Low Friction and Self-lubricating in Use Toughness and High Resistance to Repeated Impacts Long-term Fatigue Endurance
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