Special Test: Overload test: input ten times the full-scale current every five seconds, the action is repeated nine times. Each time is 0.5 seconds, after this test remains normal Vibration test: After the meter is packaged, perform 1,000 vibrations up and down 4mm per minute on the vibration plate for 10 minutes in each direction. After this test, 7-14 items remain normal. Impact test: After the packaging of the electric meter, it is dropped from a height of 30 cm on a 3cm thick wooden board. The X.Y.Z. three-direction test is maintained after this test. Reliability test: After 100,000 calibration point current inputs, the current sensitivity limit is still within the standard. Environmental impact test: temperature 50 Celsius, humidity 85%, lasts 100 hours, after this test remains normal. Terminal pull test: The terminal must withstand 1 kg of pull for 60 seconds without being affected. Parameters: Pointer swing direction: from left to right Pointer length: 28 ± 1 mm from the center axis to the needle end Pointer width: 0.45 ± 0.05 mm Electric meter use direction: Vertical Colour: Black + Yellow Material: Zinc cupronickel Size: 5.5x4.8x3.5cm Package Contents: 2 x VU Meter 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.