Upgrade Your Antminer Cooling System with this High Quality 4" Fan Duct - 120mm Size Fits DR3 L3+ S9 S9i S9J S9 SE S11 T15 S15 Z11 S17+ S17 Pro S17e T19 S19 S19J Pro DR5 D7 Z9 Models - Factory Produced for Optimal Performance - Improve Lifespan and Increase Efficiency with this Essential Antminer Accessory