RK MXZ4 is the next generation of motocross racing chains featuring Chromoly steel construction and seamless rollers and bushings. TM Racing: MC 125, MX 125, MX 144, MX 250 F, MX 300, MX 450 F, MX 530 F, SMR 530 F, SMX 250, SMX 450 F, SMX 450 Fi, SMX 530 F, SMX 660 F.
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