The asymmetrically constructed XE500 RSM can be operated without looking and even when wearing bulky gloves. The buttons for push-to-talk and emergency function are exceptionally big, but also protected against accidental use. The channel select knob can be operated even under protective clothing. The device can withstand 260 degrees Celsius for up to five minutes and with IP68 provides a very high protection standard. Five microphones assure understandable radio communications, even in very loud environments.