ı need help. 

what is the difference between  two ?

6fx5002 2ca31 1ab0-6fx8002 2ca31 1ab0 

thank you.

Hello,

6FX5002-2CA31-1AB0 = Preassembled signal cable for motors with full thread connector M23 compatible for incremental encoder sin/cos 1 Vpp 2048 S/R with C D tracks - Basic cable between motor & SMC 20 length 1 meter

6FX8002-2CA31-1AB0 = Preassembled signal cable for motors with full thread connector M23 compatible for incremental encoder sin/cos 1 Vpp 2048 S/R with C D tracks - Basic cable between motor & SMC 20 length 1 meter

6FX5002  = Predominatly for fixed installations, suitable for low mechanical loading, tested for low travel distance up to i.e. 5 m

6FX8002 = For use in cable carriers, suitable for high mechanical load, oil resistance, tested for travel distance of up to 50 m.

HTH