UX Shifters are sold as pairs and are compatible with Shimano 8 Speed Alfine internally geared hubs and a single front chainring.
Short Pull Version will work road calipers, cantilevers, road cable disc brakes or small road type mini-v brakes. If your current brakes work with Shimano or SRAM road levers select this type.
Long Pull Version will work v-brakes and mountain cable disc brake calipers. If your current brakes are a flat bar MTB brake lever and you are converting to drops select these.