Peterbilt stainless steel battery box with T-latch. Top plate is removable with 4 bolts. Front door is hinged. Oval cutouts on back allow battery wiring to pass through. Grommet recommended, not included, see item 30232. Box is 30" wide (left to right) x 16.75" deep (interior front to back), 22.125" deep (exterior from mounting holes to the back of the step), approximately 28.625" deep including step.