My company manufacturing air (outside) measuring school products: a measuring head with a ring on the assembly line, are made GGr 15, hardness of 58-62; internal air (outer) measure school products in use Please note the following: 1. rust-proof; cleaning every day before work, apply anti-rust oil; 2. wear; the probe long-term work, easy to wear; 3. verification; recommends a three-month test; mainly scaling member, 4. scrap can self-test: When measuring head wear to a certain case, the error is greater than a quarter of the DUT tolerance is recommended scrapped. For example: DUT tolerance of 20 microns, scrapped when the probe detects standard error is greater than or equal to 5 microns. The products are mainly products with pneumatic measuring gas-electric electron column micrometer supporting the use. Service 1, I solemnly promise: under normal use and service, equipment quality problems, both in the service of the three bags. 2, during the warranty period, the company services personnel to ensure product safety and reliable operation. Companies sales, service one-stop service staff keep in touch with customers to provide quality and efficient service and technical support. 3, where Zhao Ming Control Meter product comes with a lifetime maintenance services provided by the Company.