Loudon school bus camera or vehicle camera surveillance system install. At the time this DVR was one of the smallest available.  Now this school bus video or vehicle camera system DVR is 4 times larger than the new SD4m mini series.  For most applications of 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.