1. The instrument must be vertical: a 17mm wrench should be used to tighten it during installation, and the case should not be forcefully twisted; Collision should be avoided during transportation; Vacuum pressure gauge - Huai'an Senling Instrument Co., Ltd. 2. The instrument should be used in an ambient temperature range of -25~55 ℃; 3. The vibration frequency in the working environment should be less than 25Hz, and the amplitude should not exceed 1mm. 4. If the instrument reading does not return to zero or exceeds the tolerance due to high ambient temperature during use, the sealing rubber plug on the upper part of the watch case can be cut open to allow the instrument cavity to communicate with the atmosphere; 5. The range of instrument usage should be between 1/3 and 2/3 of the upper limit; 6. Isolation devices should be added when measuring corrosive media, media that may crystallize, and media with high viscosity; 7. Instruments should be regularly calibrated (at least once every three months), and if any faults are found, they should be repaired in a timely manner; 8. If the instrument is found to be ineffective or damaged due to poor manufacturing quality within six months from the date of leaving the factory under normal storage and use conditions, the company shall be responsible for repairing or replacing it; 9. Instruments for measuring corrosive media should be specified with the required conditions when ordering.