The Fitness audio digital series is our latest wireless mic receiver and transmitter combo. Operating at 2.4 Ghz the system is far from the bandwidth use for commercial TV station operation. We use our same great proprietary sweat protect-ants as well as some minor tweaks for better fitness performance. The digital processing inside the true diversity receiver means more volume, less feedback - Get your volumes much higher than before, without the annoying squeals. The transmitter has been made smaller and more functional and if you are already using one of our fitness microphones - Aeromics, Cyclemics or E-Mics wired to for fitness audio they will plug straight in.