NELD-KL Early Cracking Test Device, this product uses a 7-blade structure to induce cracking for concrete cracking tests. The blade material is 50mm angle steel, the crack observation microscope magnifies 80 times, the wind speed measurement range is 0.3～30m/s, and the wind speed analysis accuracy is 0.1m/s. External dimensions: 920×730×110(mm), all parameters meet national standards.