I purchased 4 Yate Loon fans to go inside my case and 2 of them were these models. The other 2 were the medium speed ones which I'll do a review. These fans worked amazingly great on my Thermalright Ultra Extreme 120mm heat sink fan. They blow a lot of air through the cooler and they have awesome static pressure so the air blows in a straight line. Static pressure judges how straight in a line the air from the fan blows. When purchasing for a cooler, you want this to be high. For case fans, it doesn't matter as you just want the air inside the case. The noise from these isn't bad to me at all but my case is a full tower case and sits quite a bit away from me so that could be one of the reasons that it doesn't bother me. The fans actually work pretty well also. I have to dust them and clean them about every 6 months or so to keep any dust that's built up inside the case off of them (the dust accumulates on the fan and slows down their rotation).