1. High safety: ASA test does not require the circuit board to be powered on; ASA test does not involve circuit principles and does not require the circuit to be in working state 2. Strong adaptability: ASA test does not involve the function of the components on the circuit board, so no matter what type of components the circuit is composed of, including digital, analog, mixed digital and analog, etc., it can be tested. Voltage: 4V;Internal resistance: 50R, 500R, 1K, 2K, 3K, 4K, 5K, 6K, 7K adjustable;Frequency: 20Hz, 100Hz, 500Hz, 1kHz, 2kHz, 3kHz, 4kHz, 5kHz, 6kHz, 7kHz, 8kHz, 9kHz, 10kHz, 11kHz, 12kHz, 13kHz, 14kHz, 15kHz adjustable;Size: 140x80x40;Weight: 270g for main unit Features: 1. Support dual-channel signal input 2. Support 18 adjustable frequency levels, 9 adjustable internal resistance levels 3. Adjustable B channel position 4. Support A channel or A+B channel display 5. Support trigger signal output (5V) 6. Built-in 3000mah lithium battery, using TYPE-C interface 7. 2.0 inch TFT color screen display 8. Automatically shut down if no operation is performed within 15 minutes Note: 1. The blue terminal is a multiplexed port. When the A-channel is used by default, the blue terminal outputs a 5V pulse voltage with an interval of 1 second. After the A+B channels are turned on, the blue terminal becomes the B-channel signal 2. Do not measure with power on! Before using this product, the object to be tested needs to be discharged Due to different batches, there may be differences in product appearance, color, and printed text, which not affect the use. Colour:random, don't accept the specified color Material:ABS Package Contents: 1 x Tester 1 pair x test leads 1 pair x test clips 1 x TYPE-C charging cable 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.