DC 9-24V wide voltage power supply 9-Channel one-on-one trigger interface, capable of triggering up to 9 music channels Low level trigger version, uses GND as trigger signal Supports MP3 and WAV audio decoding formats with sampling rates up to 48KHz Supports TF card storage (up to 32GB), must be formatted in FAT32 Micro-USB port for connecting to PC to download music files Built-in 30W Class D digital amplifier, can directly drive 4-8 ohm, 10-30W speakers Equipped with light/alarm output; output voltage matches input voltage, compatible with external warning lights DIP switch provides 8 selectable trigger modes Volume adjustable via potentiometer and volume control button Module size: 76 x 58mm 3-bit red toggle switch to set 8 different triggering modes; device must be restarted after mode change Dual LED indicators: green indicates power on, red indicates playback Color: Black Material: ABS Model: L30TK (Low level trigger - finished product) Package Contents: 1 x Audio player amplifier module Note: Other items not included. Slight color variations may occur due to lighting and display differences. Measurement error allowed within +/- 1-3 cm.