1. PI steel, S.S. steel, aluninum housing. best corrosion protection. 2. The aluminum fins are fastened by hydraulic expanding way, which is effective to reduce thermal contact resistance and improve thermal transfer. 40. Axial fan, low power consumption,large air volume, low noise, and far air throw. 4. evaporative temperature from -40'C~+10'C. 5. widly used in cooling room or freezing room.