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Product Name: STONE 144 BCD round Chainring, narrow and wide tooth
Material: High strength Aluminum 7075-T651, supplied by USA company Aleris who is supplier to aircraft make Airbus, Boeing and Bombardier.
CNC process precision:0.03mm
Size: 144 BCD
Speed: 9/10/11/12 speed
Fit for: 144 BCD Crank(for track bike and fixed gear)
Surface treatment: Anodize, high speed CNC