1. Implementation standard GB/T 38264-2019 “Building Curtain wall Impact resistance classification and testing Method” 2. Product features  Impact resistance indicates the ability of the curtain wall to resist outdoor impact such as hail, flying objects and birds in strong winds, and the impact of indoor personnel and items. Impact resistance is a requirement for the bearing capacity of curtain wall materials under impact load. The impact force of the curtain wall depends on the weight, form, stiffness and impact speed of the object. The device consists of a steel ball with a hanging ear, a steel wire rope connecting the rod steel ball and a bracket for fixing the released steel ball. 1. At the maximum falling height, the horizontal Angle between the suspension wire rope and the horizontal plane of the hanging point is >14°; 2. When the object is impacted and the steel wire rope is suspended in the free state, the distance between the outer edge of the steel ball and the surface of the specimen is >5mm and <15mm; 3. The geometric center of the impact object is located within a circular radius of 25mm from the impact point. 4. Steel ball quality :(1040±10)g; 5. Steel ball diameter :63.5mm 6. Support size: length 1.6× width 1.1× height 2.65m