Packing: 1/2pcs* guitar teaching aid 1 *1 electro-acoustic instrument transmitter, 1 *receiver, 1 *charging cable Specifications (guitar teaching aid) material: plastic Size: 23×19×4.5cm (length×width×height) Weight: 130 grams Application: This product does not include guitars, only guitar chord practice aids. Specifications (Electroacoustic Instrument Transmitter) Colour: Black Audio response range: 20Hz-20kHz Frequency: UHF 730MHz Transmission range: up to 50M (barrier-free), 30M (through walls) Transmission delay: less than 4ms Battery: 2 * 3.7V 600mAh rechargeable lithium battery Charging port: micro USB Product size: 110 * 45 * 15mm / 4.3 * 1.8 * 0.6in Product weight: 35g/1.2oz Packing size: 150 * 85 * 50mm / 5.9 * 3.3 * 2.0in Package weight: 150g Features (electro-acoustic instrument transmitter) Wireless transmitter and receiver kits for guitar, bass and other electro-acoustic instruments. UHF 730MHz real-quality sound transmission, anti-interface and ultra-short delay, provide you with perfect music sound. Support 4 devices to work at the same time, the transmission distance can reach 50 meters. Built-in rechargeable lithium battery, long working hours, and with USB cable, convenient charging. Plug and play, easy to use. Small and light, easy to carry. note: 1. For the data error of 1-2cm, please allow a slight manual measurement deviation. 2. Due to many factors such as display brightness and light brightness, the actual color of the item may be slightly different from the pictures displayed on the website, please understand.