Specifications: Right shifter is a trigger-type 7 speed shifter, with one lever for down-shifts and a thumb button for up-shifts. Left shifter is a friction / ratcheting thumb lever for triple cranksets. Front speed 3, rear speed 7. For 7 speed indexed SIS shifting. Optical gear display for convenient verification of gear position It works perfectly for optimum performance and maximum safety and longevity. Suitable for: mountain bike, leisure bike, road bike, folding bikes. Type: TX30 Thumb Gear Shifter Material: Plastic,alloy Features: Useful, 3x7 Speed Design, Bike Accessories Diameter: 22.2mm/0.87"" (Approx.)