Ultra high efficiency fan shroud for use with a 30mm fan. This is a bolt in part, utilizing the factory chassis screw hole just rearward of motor. Mount weight is just above 3 gram. Proven temperature reductions of up to 20-30*f. Recommended fan is the AC 30mm fan. To compliment the fan shroud, we also offer the High velocity inlet found here... Yokomo BD8 17/18 Extreme Cool Fan shroud Continue reading...