1. Adopt the latest materials in the market 2. Applicable to a of electronic equipment products 3. This tone module follows the principle of hardware priority. 4. AUX insert is AUX mode. If AUX is not plugged in, it is Bluetooth mode, and Bluetooth mode supports automatic reconnection. 5. There is a mode prompt sound when the mode is switched. Product Name: Bluetooth Tone Preamp Module Product model: -PT1 Bluetooth version: 5.0 (no occlusion, 10 meters) Signal-to-noise ratio: 90dB Input : 3.5mm audio input + Bluetooth input Output mode: AUX output (connected to active speakers and headphones) Number of channels: left and right double channels (stereo Adaptive power supply: DC5~24V/1A or more Colour:black Material:plastic Size: 67 x 68 x 21mm Package Contents: 1 assembled bluetooth module 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.