Wanhetong is a Antminer S21pro Cooling Fan manufacturer in China. We guarantee quality and ensure inventory. Martech DF1403812B2FN 12VDC 5A 140mm x 140mm x 38mm cooling fan is used to replace the damaged case fan of Antminer S21pro. When the fan is under high load for a long time, it may cause untimely heat dissipation and substandard fan speed. Timely replacement of the faulty fan can help miners dissipate heat normally. The fan adopts maintenance-free double ball bearings, with sufficient and stable air volume, and is strong and durable.