I could be totally wrong ( been that way many times in the past),but if you mean the difference between the Electra Glide Ultra Classic and the Electra Glide Classic, I think it's just the extra speakers on the Ultra. I've looked at both recently (Classic on order) and I didn't notice any difference. Of course I wasn't able to see both side by side so it may have slipped by me. I did notice that if you order a two tone bike they put the 100th Anniversary logo on the seat. Harley does make different seats also, including an air ride but it's all extra of course!
Mister Breeze