This type test hammer is used to test the concrete compressive strength of construction and bridge... Specifications: test range: 10~60 Mpa impact energy: 2.207J (0.225kgf.m) impact stroke: 75mm friction of slider: 0.5~0.8N spherical radius of impact pole: 25+/-1mm calibration value on test anvil: 80+/-2 dimension: 278*D54mm weight: 1kg