If you&';re a rider whose performance needs or riding style dictates that you run a 9-speed drivetrain, the PG-950 is the right choice for light weight, strength, and precise shifting. FEATURES a 9-speed choice for lightweight, strength, and precise shifting a Recommended Chains: PC-991 HP, PC-991 XS, PC-991, PC-971, PC-951 SPECIFICATIONS a SPEED (CS) 9s a GEARING 11-26t, 11-28t, 11-32t, 11-34t, 12-23t, 12-26t a COG FINISH (CASSETTE) Silver a TECHNOLOGY (CASSETTE) PG a COG SIZES 11-26t:11,13,14,15,17,19,21,23,26, 11-28t:11,12,13,14,16,18,21,24,28, 11-32t:11,12,14,16,18,21,24,28,32, 11-34t:11,13,15,17,20,23,26,30,34, 12-23t:12,13,14,15,16,17,19,21,23, 12-26t:12,13,14,15,17,18,21,23,26