Zk-1002 Bluetooth Amplifier Board With Tpa3116D2 Chip Bluetooth And Aux, 24V Product Details CHIP: DUAL TPA3116 HIFI Chip with AM Interference Suppression Function, 100W*2 Output Power WIDE INPUT VOLTAGE RANGE: DC 9V-24V with 5.5 * 2.1mm Interface, Laptop Power Supply Is a Good Choice BLUETOOTH AUX INPUT:User Can Directly Connect with Wireless Bluetooth 5.0, or Choose the 3.5MM Headphone (Line in) Way PROTECTIVE FUNCTION:Over-voltage Protection, Under-voltage Protection, Over-heat Protection, Short-circuit Protection, This means that the Bluetooth amplifier board is not easily damaged TIP: adequate output power is required when the audio input is sufficient and the power supply voltage/current is sufficient, the relative power will be higher. Different impedance horns will have different output power.In the case of sufficient voltage and current, the larger the impedance horn, the smaller the relative sound power, please pay attention! Payment We accept PayPal and credit cards via PayPal. Taxes - US We collect sales tax, as required by law. Shipping We make every effort of shipping within 3 business day of payment clearing. The estimated delivery time is 2 - 5 business days from the shipping date. Policies If you do need to return your item, please contact us via email (you will receive an email when your product ships with additional details - Subject: Important information about your purchase). You will then be provided with a return shipping label and packing slip. Pack the item carefully. Include the packing slip, apply the shipping label, and return the item within 30 business days of the date you request a return, or your return will be canceled. Once we receive your order we will inspect the return. Please allow up to 5 business days of receiving the returned item for your refund.