Integrated microphone capsule design, featuring trusted SM58Automatically links with GLX-D wireless receivers for seamless frequency changingUp to 16 hours of continuous, rechargeable use with Shure proprietary lithium-ion rechargeable batteriesOperating Range: Indoors: Up to 100 feet (30 m) typical, with a maximum of 200 feet (60 m) under ideal conditions, Outdoors: Up to 65 feet (20 m) typical, with a maximum of 165 feet (50 m) under ideal conditionsSophisticated design with durable, lightweight construction