Shure GLXD14R+/MX53 Digital Wireless MX153 Headset Microphone Rack System, Z3 2.4, 5.8 GHzShure GLXD14R+ MX53 Digital Wireless MX153 Headset Microphone Rack System, Z3 2. 4, 5. 8 GHz The new GLX D+ Dual Band Wireless Rack System features the premium MX153 Headworn Earset for high quality vocal performance applications and the GLXD4R+ half rack receiver. The perfect combination of the automatic frequency management with the new Dual Band Technology provides reliable and consistent performance while Shure proprietary Lithium Ion rechargeable