Based on the PAM8403 digital amplifier chip, this amplifier board delivers fourchannel audio output (4x3W) and is powered from a 5V USB source. It is suitable for projects using Arduino, MP3 modules, Bluetooth modules, or USB power banks. Key benefits Four independent 3W channels: drive four speakers (4Ω–8Ω) with one compact board, enabling stereo plus stereo or multizone setups. Flexible compatibility: ideal for Arduino projects, MP3 players, Bluetooth modules, and USB power banks thanks to 5V USB power. Efficient ClassD amplification: provides efficiency with lower heat generation for continuous use. Durable, easy integration: compact PCB design with onboard capacitors, screw terminals, and a USB power port for straightforward wiring. Reliable performance: designed for low noise and low distortion, with builtin shortcircuit and overheat protection for longterm use. Important specifications and features Output: four independent 3W channels (4x3W) Load impedance: suitable for 4Ω–8Ω speakers Channel configuration: supports stereo + stereo (L1/R1 + L2/R2) or multizone audio Power supply: 5V USB powered Amplifier technology: ClassD digital amplification Construction: compact PCB design with onboard capacitors, screw terminals, and USB power port Performance safeguards: low noise, low distortion, efficiency; builtin shortcircuit and overheat protection Use scenarios Multiroom or multizone audio projects: run two stereo pairs to different rooms or zones from a single board, controlled by a central microcontroller or audio source. Arduinobased audio projects: pair with Arduino or compatible MP3/Bluetooth modules to add amplified sound to DIY gadgets, kiosks, or demonstrations. Portable USBpowered speakers: integrate with a USB power bank to create compact, batterypowered speaker systems for events or demonstrations. This description remains consistent with the original product's brand, specifications, models, and functions, while presenting the information in clear, customerfocused language.