1.Instructions Zc3-a concrete test hammer, in accordance with jgj/t23 technical regulations, is used for detecting the concrete compressive strength within the range of 10-60mpa and has the system standard energy of 2.207j. The medium-sized resiliometer with pointer direct-reading type indication system is manufactured under the supervision of the chief formulation unit of national regulations on measurement and verification of concrete resiliometers (jjg817) and the technical regulations on rebound-method detection of concrete compressive strength, the industry standard. 2.Main specification Length of pointer20.0.2(mm) Friction force of pointer0.650.15(n) Spherical radius of bounce rod end251.0(mm) Stiffness of bounce tension spring785.30.0(n/m) Decoupling position of bounce hammer00n scale line Impact length of bounce hammer750.3 Takeoff position of bounce hamme0n graduated scale Fixed value of steel anvil82 (80-81 for our delivery products)