With the X.5 rear derailleur, SRAM strives to keep the look and feel high-end in an affordable entry-level package with an alloy B-knuckle and links and a high-strength grilon composite P-knuckle. Direct Route Technology makes for tidy cable routing, which improves shifting feel and quickness while 1:1 Exact Actuation performs reliably in any condition, which means that X.5 is only a touch behind its big brothers in the performance department. A pretty small price to pay considering how high SRAM's upper end sets the bar if you ask us, making X.5 a good match for recreational off roaders and flat bar commuters with no need for the top-of-the-line.