Shimano sales constitute an estimated 70–80% of the global bicycle component market by value. Its products include drivetrain, brake, wheel and pedal components for road, mountain, track and hybrid bikes. The components include crankset comprising cranks and chainrings; bottom bracket; chain; rear chain sprockets or cassette; front and rear wheel hubs; gear shift levers; brakes; brake levers; cables; front and rear gear mechanisms or dérailleurs. Shimano Total Integration (STI) is Shimano's integrated shifter and brake lever combination for road bicycles. The Italian firm Campagnolo as well as US based SRAM are Shimano's primary competitors in the cycling marketplace.