HollowGram SL wheels rise to even higher speeds. DT Swiss Aerolite spokes – shaped for lower drag without losing strength – are paired with custom HollowGram hub shells. Ultra-reliable DT Swiss 240 EXP internals at the rear bring a 36-tooth freehub ratchet for instantaneous pedaling engagement while minimizing mechanical drag. In HollowGram speak, SL means weight is lowered, responsiveness is increased, and aerodynamic efficiency is maximized.