4IIII power meters are used by: Marcel Kittlel riding for Quick-Step Floors Cycling Team   Peter Sagan riding for Bora-Hansgrohe Pro Cycling Whether you’re a pro or simply training hard, PRECISION power meters deliver industry-leading accuracy, highly dependable cadence data, 3D power meter technology capable of measuring tri-axial strain on your crank arm. Designed to be durable and lightweight, compatible with  ANT and Bluetooth head units, PRECISION helps you train harder and smarter.  PRECISION Factory Install is installed on your existing left crank.