The coatings on buildings often fail due to the cracking of the substrate. The XB-OTS-CO303 anti-crack fatigue tester is designed according to the “Anti-crack fatigue test” project in the latest standard HG/T 4343-2024 “Water-based Colorful Architectural Coatings”. The left and right parts of the cracks of the test plate can be moved horizontally or relatively reciprocating, and the relative moving distance, cycle times, and moving speed can be set.