ITEM NAME:PAM8403 2X3W Mini Audio Class D amplifier board 2.5-5V input FT Features: 1.Machine Electricity: 2.5 V - 5.5 V. Attention: Power supply needless superfluous 5.5 V, power supply positive / negative unnecessary connection. 2..1pc PAM8403 2X3W Mini Audio Class D amplifier board. Successfully placed board disconnected electric circuit, mold clasp Short path overflow protection Coolant protection.