Hi, as far as it shows it says : 8JJ 15 inch on the inner rim and I think the word Brazil, 7/ 93 which I assume is the manufacture date but there is a sticker which says it has a 1000lb rating, sorry about the pics, damm thing never works for me, I usually have to get one of the grandchildren to set the central heating! I measured from the inner contact face to the rim edge as best I could and got 3.5" is that the off set?