Genuine Echo Chainsaw Chain 3 PACK Part 20LPX78CQ (SAW CHAIN 20") Where Used: · CS-450P S/N: C06312001001 - C06312999999-->Guide Bar, Saw Chain · CS-450P S/N: C06413001001 - C06413999999-->Guide Bar, Saw Chain · CS-500P S/N: C19312001001 - C19312999999-->Saw Chain, Guide Bar · CS-500P S/N: C19413001001 - C19413999999-->Saw Chain, Guide Bar · CS-501P S/N: C36712001001 - C36712999999-->Chain, Guide Bar · CS-501P S/N: C36813001001 - C36813999999-->Chain, Guide Bar · CS-501P S/N: C68515001001 - C68515999999-->Chain, Guide Bar · CS-520 S/N: C07113001001 - C07113999999-->Standard Guide Bar, Saw Chain, Kick Guard · CS-520 S/N: C09312001001 - C09312999999-->Standard Guide Bar, Saw Chain, Kick Guard · CS-550P S/N: C10712001001 - C10712999999-->Standard Guide Bar, Saw Chain, Kick Guard · CS-550P S/N: C14113001001 - C14113999999-->Standard Guide Bar, Saw Chain, Kick Guard