These units were the early product versions from ATX fitted with the large Hard Drives for storage that offered massive storage capacity at the cost of reliability. Aside from mounting the units on their side, the installer failed to secure the lock box properly and when the fragile mounting system failed it permitted the lock box and DVR to smack back and forth with every acceleration nd braking inertia, with a full 3" swing span permitting more than enough G force to destroy almost every Hard Drive mounted in this fashion in short time. For school bus cameras, digital bus video cameras, vehicle camera, mobile video surveillance systems, digital in-car video camera, in-car camera, bus camera surveillance the best value is 100% Solid State digital like the SD4m or SD4 series.