The Walker's Xcel 500 Bluetooth Electronic Earmuffs offer a variable dynamic sound suppression system. There are four listening modes: Universal Speech clarity mode Hi frequency power boost. Bluetooth connectivity allows you to connect to your mobile device as well. - Bluetooth Connectivity - Variable Dynamic Sound Suppression - Hi Gain Omni Directional Mics - Voice Mode Navigation - Wind Noise Reduction - Auto shut off - Ergonomic head band design - Controls moved to headband - Less holes in the muff cups to improve NRR - Rubber bumpers on lower cup - Low battery warning