Features: * Long distance: UHF wireless transmission distance can reach 50-60m (165-200ft), no need to worry about interference. * Multi-channel: automatic frequency matching, plug and play, each microphone has 50 channels to choose from, 4 microphones have a total of 200 channels. * Volume Knob: Each mic has its own drink knob control to balance vocals according to your usage and scene needs. * Compatible: Compatible with various audio equipment, such as: effects, amplifiers, mixers, speakers, rod speakers, etc. Specification: Receiver Number of channels: 4 channels Sensitivity: -80dB Audio output: Balanced all-in-one Power requirements: DC 12V/1000mA Size (W*D*H): 210*145*40mm Microphone: Channel: 50 (CH01-CH50) Carrier frequency range: 533.1-598.1MHz Working range: 60m (under typical conditions) RF output: 10mW Normal deviation: ± 22 kHz Dynamic Range: 90dB Battery Power: 2 1.5V AA batteries Size: 258 * 50mm Packing included: 1 x UHF wireless receiver 4 x Handheld Wireless Microphones 4 x Microphone Protection Rings 1x 1/4" audio cable 1 x AC/DC Power Adapter 1 x User Manual (English) Note: 1. Due to manual measurements and slight color variations, please allow 1-3 cm (0.4-1.18 inches) difference to suit different display settings. 2. Due to the light and screen difference, the item's color may be slightly different from the pictures. Please understand.