The SRM Wireless Powermeter SRAM S975 (8 strain gauges) has an accuracy of ±2%.
The SRAM Wireless PowerMeter takes a 130mmBCD large chain ring and small chain ring. It can be set up with standard 53/39 and only fits frames with a BB30 bottom bracket.

Includes:

• SRM Wireless PowerMeter
• SRM PowerControl
• Cranks
• Chainrings
• Heartrate belt
• Wireless speed sensor
• Handlebar clip
• Software
• Manual
• Multi-charger (works with both 110V and 220V)
• USB download cable

Note: Bottom bracket is not included!