The Flex-Fit Quattro MB344SP is our most advanced quad 2.5” HDD / SSD bracket and we've designed this unit to be both user-friendly and highly flexible. The Flex-Fit Quattro MB344SP accepts up to 4 x 2.5” SATA HDD / SSD drive from 7mm to 9.5mm in drive height, which uses a completely new tool-less drive installation design with an advanced drive stabilizer system to simplify our drive installation process –all you need to do is insert the drive, and push inwards until an audible “click” is heard to indicate that the drive is securely installed. The drive stabilizer kits will automatically conform to different drive height and adjust the drives in place while providing full access to the drive. Lastly, the easy to access drive eject button allows for quick hard drive swapping in a matter of seconds without removing the entire bracket from the chassis. The best part about this bracket is it's completely tool-less drive installation –just insert the drive and you're set. It does not get any easier.