Tighten the four spring screws to tension the clamping spring.
Install a hard drive with the flat surface touching the heatsink.
Secure the hard drive with four screws on the sides.
Loosen up the spring screws to ensure the heatsink and the hard drive are closely contact.
Install the air intake panel and secure it with screws.
Install the completed unit into the drive bay and secure it with screws.
Connect the fans to power supply.