WH220 11/8/2017 Category: Products, DX Series Digital Wireless Systems, Wireless Headsets, Wireless, DX100 Digital Wireless Systems, Wireless Headset, DX121 Digital Wireless Systems, Wireless Headset, DX210 Digital Wireless Systems, Wireless Headset, Headsets & Accessories, Headsets, DX Series All-In-One Single- or Two-channel operation 2.4GHz frequency range Hands-free communications 5 kHz wide band audio Single-ear, light-weight design Rugged and reliable Up to 12 hours of battery life