1. The power supply of the power amplifier board requiresDC 12-24V 3A regulated switching power supply (the battery and charger, transformer and AC switching power supply cannot be used for testing) 2. DC12V 3A (above) power supply, the maximum output power is 2*15W /8 ohms (full volume may be distorted after turning on) 3. DC24V 3A power supply, the output power can reach up to 2*26W /8 ohm continuous power (4 ohm speakers may be ) (all volume may be ) 4. Do not connect to a battery with a standard 24V, because the battery may 25V after being fully , and the capacitor on the board is 25V, there is a risk of explosion 5. Do not connect the 24V battery of a truck, because the charging voltage reaches 28-32V when the truck is on fire, and it will burn Product name: Bluetooth 5.0 power amplifier Bluetooth version: JL-AC6925A-5.0 Power supply voltage: DC12-24V Supply current: 3-5A Output power: 26Wx2/ 8 ohm Output impedance: 8 ohms Colour: green Material: plastic Size: 96 x 48mm Package Contents: 1 x Amplifier Board Note: There is no manual, confirm the of Bluetooth USB circuit board connection placing an order. Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real . The measurement allowed is +/- 1-3cm.