Manuals and User Guides for Polar Electro G590/G591/G592/G593/G594/G595/U632/U633/U634/U635/CC663/CD616/GD879/GD880/. We have 1 Polar Electro G590/G591/G592/G593/G594/G595/U632/U633/U634/U635/CC663/CD616/GD879/GD880/ manual available for free PDF download: Instruction Manual