Features: A speaker expansion board designed specifically for micro: bit, which can turn your microcomputer development board for micro: bit into a music player; It also supports Arduino development and is compatible for 3.3V and 5V Arduino boards. On-board hifi NS8002 power amplifier chip. Support volume adjustment function. Supports headphone interface output. Provide comprehensive documentation manuals (for Micro: bit graphical-routines/Python-routines/Aruino-routines, user manuals, etc.). Specifications: Material: Printed Circuit Board Size: Approx. 36.52x43.44mm/1.44x1.71inch Through Hole Diameter: Approx. 3.2mm/0.12inch Working-voltage: 2.0V~5.5V Protection-function: automatic protections Output-voltage: standard Voltage-drop: standard Package Includes: 1x Speaker Expansion Modules 3x Clip Cord 1x PH2.0 3Pin Connection Cable note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.