... ,truss. Nondestructive concrete testing instrume HT-225A Concrete Test Hammer Detail informationSpecifications: ModelHT-225ANominal kinetic energy2.207J(0. ... for impact hammer75mmImpact surface hardness value between impact hammer and rodHRC59-63Maximum breakout friction of pointer system0. ... D 5873, NFP 18-417, B 15-225, JGJ/T 23-2001, JJG 817-1993Dimension60x280mmNet weight1kg Concrete Test Hammer