A seamless blend of form and functionality, Sennheiser RS120 II RFWireless Headphones offer high-quality sound, lasting durability,and comfort fit. They provide excellent wireless RF reception withina range of up to 100 metres. With three selectable RF channels, theseover-ear wireless headphones let you switch to another frequencyband when reception on the current band drops. They also featureconveniently placed controls for easy operation. The transmitterhas a metal cradle on top to safely store and recharge these Sennheiserwireless headphones.