Features Reliable Alarm Performance - This active buzzer module features an internal oscillation source, providing consistent alarm functionality as soon as it receives power Easy Program Control - With compatibility for single chip microcontrollers, this buzzer alarm module can be easily controlled with high and low level signals for versatile applications Robust Drive Capability - Powered by a 9012 transistor, this beeper buzzer module ensures strong performance and durability, making it ideal for various electronic projects Features: 1、This active buzzer has internal oscillation source, so it will alarm as long as being energized. 2、Convenient program control, single chip microcomputer high and low level can make it sound, better than a passive buzzer. 3、Module is driven with 9012 transistor. 4、Designed with holes for fixing with bolt, convenient to install. 5、External connection of 3.3V-5V voltage, can be directly connected to 5V micro-controller and 3.3V micro-controller. Specification: Features: This active buzzer has internal oscillation source, so it will alarm as long as being energized. Convenient program control, single chip microcomputer high and low level can make it sound, better than a passive buzzer. Module is driven with 9012 transistor. Designed with holes for fixing with bolt, convenient to install. External connection of 3.3V-5V voltage, can be directly connected to 5V micro-controller and 3.3V micro-controller. External connection of GND3 out external micro-controller IO port. Specification: Working Voltage: 3.3V-5V Module Interface: 3 wire system Size: 3.8*1.3cm/1.5*0.5in Quantity: 5pcs Weight: 4g(approx.) Package Includes: 5 x Buzzer Modules Package List