PowerTap SL Rear Hubs are pro level power measurement hubs featuring a carbonalloy hub shell and wireless transmission. The SL hub weighs 412 grams. Wireless 2.4 GHz transmission with ANTSport 15mm alloy axle with CarbonAlloy Hub Shell Must purchase Compatible ElectroPack and skewer separately 2009 CPU's will work with current and older hubs but 2009 hubs will not work with older CPU's HubBrake Compatibility Rim Brake Rear Axle Type 10x1 Color Silver Cass
)
