What shimano chains are available?

For the most recent example, in 2003 Shimano introduced "Dual Control" to mountain bikes, where the gear shift mechanism is integrated into the brake levers, and reintroduced the "Rapid Rise" rear derailleur which works in the opposite direction to traditional derailleurs. This development was controversial: critics viewed it as an attempt to monopolise the mountain bike components market: the use of Dual Control integrated shifting requires the use of Shimano brake levers, and, although other brand mechanical brakes are compatible, this makes it impossible to use other brand hydraulic disk brakes, locking competitors out of the premium end of the market. Additionally, the Rapid Rise derailleur is believed to work more effectively with the Dual Control system, further restricting users' choice of componentry. However with their 2007 product line, Shimano moved back to making separate braking and shifting components fully available in addition to the integrated "Dual Control" components, a move often attributed to the success of the Sram group's drivetrain and brake components.