Product Name: FULINDA KP-640 UHF Dual Channel Wireless Microphone Model: KP-640 Brand: FULINDA Warranty : 12 Months KP-640 Wireless One-to-Four Microphone Features: A highly stable model developed and designed for fixed installation places such as KTV. Backlit LED display indicates RF and AF signal strength, battery status, working status of frequency, frequency group/channel, etc. Digital audio code locking technology is adopted to effectively block the noise interference in the use environment. Using the latest infrared automatic frequency (IR) technology, the setting and operation are easier. Independent hidden system lock key. One key to lock. Convenient and practical. The microphone can be used interchangeably, with strong versatility, all-metal plated tube body, strong, anti-drop and wear-resistant. Comprehensive parameters: Frequency range: 640MHz-690MHz Number of channels: 200 Channel spacing: 300KHZ Frequency Stability: ±0.005% Dynamic range: 100db Maximum offset: ±45KHZ Audio frequency response: 40HZ-18KHZ (±2db) Comprehensive signal-to-noise ratio: >105db Comprehensive distortion: =0.5% Receiver: Antenna Access: BNC/50O Sensitivity: 12dBuV (80db S/N) Sensitivity adjustment range: 12-32dBuV Spurious suppression: =75db Maximum output level: +10dbv Power supply mode: DC 12V 205mA input Transmitter: Output power: 12V/ 250mA Audio frequency response: 40~18,000Hz, (+1 dB, -3 dB) Spurious Suppression: -60db Scope of work: 50 meters in straight line distance. Note: The actual range depends on RF signal absorption, reflection and interference. We have a physical shop located in Auckland Airport Oaks/ Mangere area, you are welcome to come & pick up. (opening hours: Mon-Fri 10am-6pm, Sat 12pm-5pm; closed on Sundays & public holidays)