Sram rival black 10 speed short cage rear derailleur sacrifice nothingnot durability dependability or performance nothing the sram rival rear derailleur matches srams exact actuation with tried and true competition proven design and construction exact actuation delivers even gear changes over the entire shifting range via a precise 3mm adjustment from gear to gear the sram rival rear derailleur weighs only 188g but features an all aluminum b knuckle inner link and cage that can stand