Features: Dual USB ports, support 3.1A quick charge, built-in over-current and short-circuit protection, safer to use. Support bluetooth wireless connection and U disk playback, lossless sound quality, give you a nice music experience. Support hands-free calls, built-in noise reduction microphone, clear calls, answer/reject/recall in one key. With digital display, real-time monitoring of battery voltage and frequency, easy to read ans safer to drive. With power-off memory function, automatic connection after power-on, memorize frequency, more intelligent. It is suitable for most 12-24V mainstream models on the market.Specifications: Color: Black Material: ABS Work Voltage: 12-24V Output Current: 0-3.1A Frequency: 87.5-108MHz Support Distance: About 10 Meters BT Version: BT 5.0 Item Size: 45 * 36 * 73mm/ 1.8 * 1.4 * 2.9in Item Weight: 30g/ 1.1oz Package Size: 53 * 53 * 73mm/ 2.1 * 2.1 * 2.9in Package Weight: 40g/ 1.4ozPacking List: 1 * MP3 Player 1 * Manual