Shure SLXD4Q+ Quad-Channel Digital Wireless Receiver - G57The SLXD4Q+ is a quad channel digital receiver for use with SLX D transmitters. With the crystal clear audio and rock steady RF that SLX D provides, the SLXD4Q+ features a wide 138 MHz tuning range and easily pair with SLX D bodypack, handheld and plug on transmitters. Use audio output summing to set and manage wireless output levels and use RF cascading to quickly scale up compact and powerful multi channel wireless systems for every application.