Use digital amplifier technology: low distortion, low noise, high efficiency, good sound quality. Five audio options: two public audio (Cabling input) and three local source (built-in: FM + TF card + USB function). Radio: install full-automatic digital FM radio internally, 30 radio stations storage . Volume Adjustment:32-level electronic volume control. Adjust the high and bass sound [Product Technical Specifications] • Power supply: AC230V/110V • Output power: 12W+12W (MAX) • Input impedance: 47KΩ • Output impedance: 8Ω • Total Harmonic Distortion: 0.03% • Frequency Response: 20Hz-20KHz • Infrared remote control distance: ≤ 10M [Product Using Reminder] • Supporting bottom box: embed the 86*86MM standard bottom box. • Cable: Four kinds of cables are used in the system: First,wire: 1-2 square; Second, audio cable (two-core shielded cable: commonly known as the microphone cable): RVVP2 * 0.3 RVVP2 * 0.5 RVVP2 * 0.75; Third, speaker cable: RVH2 * 100 RVH2 * 200. Fourth, antenna: any core wire is ok,such as a copper wire. • Wiring reminder: When there are multiple points (multiple rooms, multiple products), the wiring is in parallel, or connected through the junction box • Details to see the product manual. Color: White Material: plastic Package Contents: 1*amplifier 1* Remote Control(Without 1 button battery) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.