VFD253 integrates mutiple functions into a whole. As an audio spectrum analyzer: adopts dedicated green VFD display screen with 25 x 15 high resolution, the accuracy of each frequency band. As a Bluetooth receiver and audio switcher: besides microphone pickup, also with Bluetooth 5.0 and 2 groups of 3.5mm AUX input, works perfectly with your phone/PC/game player/amplifier/speaker etc. As a high-precision clock: using RX8025T built-in crystal oscillator whose clock accuracy is 3ppm, year error within 1 minutes, very cool and interesting. Wide frequency range & special AGC display: 80Hz-16KHz frequency sweep, high-precision display even can do frequency point test. Speical AGC algorithm and customized output curve, ideal visual effects even the input signal is in a small to large range, avoid that no display when input low and display in full screen when input high. Many adjustable items & display effects: gain, brighntness, falling speed of main light column, holding time and falling speed of the can be adjusted separately. 5 music spectrum display mode and 2 clock display mode, all settings with power-off memory function, no need to set again after restarting. Attractive looking and convenient use: with remote control, easy to adjsut all settings and see the music level status in real time and every slight change of sound. Warm tips: 3.5mm AUX1 and 3.5mm AUX2 cannot input at the same time, only one audio source channel (MIC / Bluetooth / IN1 / IN2) can input at a time. Display screen: VFD (Vacuum Fluorescent Display) Resolution: 25 x 15 Frequency range supported: 80Hz-16KHz Display item: music spectrum / clock Audio signal input: MIC / Bluetooth 5.0 / 2 groups of 3.5mm AUX Audio signal output: 1 group of 3.5mm AUX Color: Black Material: Acrylic + Aluminum Alloy Package Contents: 1 * Audio Spectrum 1 * USB Cable 1 * Remote Control (without 2*AAA batteries) 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.