I needed a SSD tray to put three ssd drives into the space of two 3.5" bays. These fit my drive sleds for my Corsair 650D case, but should fit in any 3.5inch drive solution. I provided the option to mount a 40mm fan to the tray if desired. I did not print or test the fan option myself. Mount the fan housing with m3 screws on the bottom of the tray. The bottom ssd drive screws from the bottom, the next two from the sides.