Amazon.com: SHIMANO ST-EF500-4 Bicycle Shift/Brake Lever Set - 3 x 7 Speed, EZ-Fire Plus, 4F-Alloy, for V-Brake - Black - ESTEF5004PV7A3 : Sports & Outdoors
Shimano Di2 Ultegra ST-R8060 Time Trial Brake Lever Set - Tri Town Bicycles
Mountain bike groupsets: everything you need to know - BikeRadar