Feature: 1. It has good sound quality, suitable for upgrading and modifying idle speakers and DIY production. 2. The operation is simple and use high quality material to effectively avoid corrosion and wear, it is durable. 3. Wide range of application, Bluetooth version 4.2, it is compatible with all mobile phones and Bluetooth adapters on the market. 4. The Bluetooth audio receiver board already has dual 5W power amplifier circuit, which does not need to connect additional power amplifier. 5. The maximum operating current is 5V2A, powered by a regulated 5V2A or higher, the sound quality is better. Specification: Item Type: Bluetooth Amplifier Board Operating Voltage: DC 3.7-5V Maximum Operating Current: 5V2A (Powered by a regulated 5V2A or higher, the sound quality is better.) Speaker: 2-8 ohms, 3-10W (It is recommended to use 4 ohm 5W or 4 ohm 10W speaker. The output is stereo.) Bluetooth Version: 4.2 Product Size: Approx. 40 x 20 mm / 1.6 x 0.8 in Operation: Start the cell phone Bluetooth, scan the device and find the ''DW-CT14+'' to click connection. Package List: 1 x 3.7-5V Dual Plate Amplifier Board DIY Bluetooth Speaker Modification Module3 x Flat Cable Note: 1. The charging interface of this product is a current limiting charging mode without charge management. For your safety, be sure to use a regular lithium-ion battery with a protective plate, which can cause loss due to improper use.2. This product will automatically shut down after 10 minutes in standby mode, you need to power on again.3. It is suggested that a 3.7-5V lithium battery (the lithium battery needs a protective plate. It can charge a lithium battery with a USB rechargeable battery, and the USB port can be used as a power supply port.) or a 5V adapter be used for power supply. It can not use voltage and current unstable power supply, such as dry battery, portable charger, multi-function transformer and so on.4. When the Bluetooth board is installed, the antenna should not be close to the metal parts so as not to affect the transmission distance.