VEVOR Underbody Truck Box, 60"×17"×18" Pickup Storage Box, Heavy Duty Aluminum Diamond Plate Tool Box with Lock and Keys, Waterproof Trailer Storage Box with T-Handle Latch for Truck, Van, Trailer

It has to be a misprint. No way it could be 7.5" tall. So it is the larger number. I can't even recall any box I ever seen that short while also being 60".

For the Underbody Truck Box, the height is 18”.

I believe it’s the 18. I’m not by my truck to give exact but it’s definitely not 7.5 atleast not mines. I will say this if you are planning on installing it under the underbody of a truck you must not should but must use the stabilizers they are sold separately. This units metal is thin and any weight mixed with normal travel, winds, shaking etc will cause it to rip right from under the truck. Had this experience.

I am using this box in a vertical position on my gate opener and it works fine. Box is thin walled and may not hold up vertically if mounted on a truck.

I vae mine sitting on the floor horizontally, the door is slightly smaller that the box on all corners so letting it sit vertically should not be a problem door will still operate

Yes it can,with the box on it’s side setting on the floor the door would be 1”off the floor

I would say yes, but I would remove the chain on the bottom side of the door so it doesn't get trapped in when closing.