4iiii Precision Ultegra R8000 Left Arm Powermeter | Merlin Cycles
Amazon.com: 4iiii Precision Powermeter Left Side | Shimano Ultegra R8000 | 172.5mm | Measures Each Pedal Stroke with 3 Strain Gauges : Sports & Outdoors
4iiii Precision3 Shimano R8000 Power meter left
Amazon.com: 4iiii Precision Powermeter 3 Left Side | FC-R7000 | 165mm | Measures Each Pedal Stroke with 3 Strain Gauges | IPX7 Water Resistance | Up to 800 Hours Battery Life | Ultra Low Profile : Automotive