Lossless professional sound quality ensures high-quality o transmission. 2.4GHz wireless transmission frequency band supports 24bit/48kHz sampling rate for clear sound. Up to 30 meters of effective transmission distance, eliminating cable constraints. Supports one transmitter connecting multiple receivers for simultaneous transmission. Transmitter offers up to 24 hours of battery life; receiver provides up to 6 hours, suitable for extended use. Features four working modes: left channel, right channel, stereo, and mute, compatible with various devices. Receiver allows volume adjustment and mute control; transmitter includes one-button mute function. Sampling rate: 24bit/48kHz lossless digital transmission Wireless frequency band: 2.4GHz Effective range: 30 meters outdoor Power supply: Built-in lithium batteries, rechargeable via USB Type-C Recommended charger: 5V1A Frequency response: 20–20kHz, ±1dB/-3dB Battery specifications (TX/RX): Transmitter 803060, Receiver 402030 Battery capacity (TX/RX): 1800mAh / 200mAh Nominal battery voltage: 3.7V Transmitter dimensions (mm): 95.04(L) x 39.7(W) x 38.12(H) Receiver dimensions (mm): 31.1(L) x 41.5(W) Weight: Transmitter 75g, Receiver 15g Color: Black Material: ABS Package Contents: 1 x Wireless Ear Return Transmitter 1 x Wireless Ear Return Receiver 1 x Charging Compartment Note: Light reflection and display differences may cause slight color variation between image and actual item. Measurement error allowed within +/- 1-3cm.