Working voltage: 3.3~30V; Frequency range: 1Hz~150KHz Frequency accuracy: The accuracy of each range is about 2%; Signal load capacity: The output current can be around 5~30ma Output amplitude: PWM auxiliary value is equal to the power supply voltage; ambient temperature: -20~+70℃ Automatic data storage - all parameters are automatically saved after setting and not be lost when power is turned off. Other features----With LCD display to display frequency and duty cycle values; with housing; PWM output, frequency and duty cycle can be set independently through buttons; frequency value is automatically switched in 4 levels with high accuracy. Colour:Photo Color Material:plastic Package Contents: 2 x generator Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.