This item is exactly what it means: a reliable helmet interphone. I use this device since two years an it is working great. The sound is loud and clear even over 120 km/h. Fully charged provide a valid link at ~ 200 - 250 m, after 6-7 hours the distance decrease at ~ 60 - 70 m. It is easy to mount and maintain.Bottom line, it is a perfect deal. The device give satisfaction for every cent from its price.