From the seller:

**TA4F-Condenser-Earset-Double-Earhook-Microphone Included** Shure QLXD4-G50 Wireless Microphone Digital Receiver - G50 Range QLXD1 Wireless Bodypack Transmitter quickly syncs with a wireless receiver over IR at the push of a button and maintains a clear, uninterrupted signal over its entire range. It features transparent 24-bit digital audio quality and incredibly efficient RF spectrum usage, the QLXD1 Wireless Bodypack Transmitter is ideal for wireless vocals and instruments in mid-size presentation spaces, music venues, and houses of worship. Features: Works with QLX-D Digital Wireless Systems Offers up to 9 hours of continuous use with 2 AA alkaline batteries or up to 10 hours of continuous use with Shure lithium-ion rechargeable batteries Includes QLXD1, 2 AA batteries, black zippered pouch, and user guide Over 120 dB of dynamic range: no transmitter gain adjustments needed AES 256-bit encryption for secure transmission Optional Shure SB900 lithium ion rechargeable battery reports remaining runtime in hours and minutes External charging contacts for docked charging Backlit LCD with easy to navigate menu and controls Selectable display mode showing group/channel, frequency, or battery runtime 4-Pin male mini connector (TA4M) Rugged metal construction Detachable 1/4 wave antenna Frequency and power lockout Specifications: Radio Frequency Range: 20 Hz–20 kHz Battery Requirements: 2 AA alkaline batteries or SB900 Lithium-Ion Rechargeable Battery Battery Life: Shure SB900: Up to 10 hours, Alkaline: Up to 9 hours Typical Operating Distance: 100 m (330 ft) line of sight