Size: 30mmx18mmX18mm/1.17" x0.52"X0.52"(inch) (approx)

1. Onboard SG3525A PWM control chip.

2. On-board 78M05 regulator chip, providing a reliable reference voltage.

3. Onboard two precision adjustable resistors, R3 controls the duty cycle, R4 control frequency.

4. On-board power indicator.

5. The working voltage: 8V ~ 12V.

6.Oscillator for frequency bubble Wai find: 100-10KHz