Buy Screen Protector for Polar M400 (Screen Protector by BoxWave) - ClearTouch Anti-Glare (2-Pack), Anti-Fingerprint Matte Film Skin for Polar M400, Polar M400, M430 Online in USA. B0160BSN8S
Polar M400 Review | GearLab
Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
Polar M400 | Polar M400 | Mikko Miettinen | Flickr