Yes Norm, checked, and it is a Gel tech. I don't know what size, but the dimensions are 9in long, 8in high, and 5.5in wide, that is why it is on it's side, to get it to fit under the rear jump seat. I would take a picture, but I am a bit imbarrassed about my mickey mousing on that one, as it was all temporary, and 5years later, still that way
Greg, never heard of the gel gassing, the guy selling them to me said they are completely sealed, that is why I can lay it on it's side, he said you could mount it upside down if you want. Never had any battery smells inside the cab, but could be just that the 40series cabs are so drafty

I would buy one again, and I think I probably will buy another for the inside of the cab of my mine truck.
Cheers,
Deny
PS norm, those batteries I got from you are still in rusty, and it sits for a long time (even through our -40 winters) and starts up first try every time I want to move it.