4 Channels, 4 X 50W Large Power Hifi Amplifier Board, Digital Audio Amplifier Product Details [4 Channels High Sensitivity] This digital audio amplifier board adopts 4 channels to create a stereo surrounding sound. Gives you greater hearing enjoyment. [Hi-Fi Stereo Sound] Maximum output power of 4 x 50W gives you a Hi-Fi stereo sound. [Multi-level Protection] Built-in over voltage protection, over heat protection, undervoltage protection, DC detection and short-circuit protection of this digital power amplifier board helps provide a safe amplification. [IC Smart Cooling] When temperature exceeds 25, the fan will be turned on automatically to dissipate high heat rapidly and quietly. [Stable Current] This digital power amplifier board makes sure a stable current, thus ensuring the stability and smoothness of sound. 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.