It was my understanding that the Ultra & LTD low models had the same front end as a standard, non low model other than the addition of the profile low, single cartridge kit. I was browsing the parts book and I see this is mostly the case except for one thing. The low model shows a different part number for the upper fork tube, or stanchion (the fixed bit) compared to the standard. As you can install the lowering version of the kit from the P&A book on the standard height bikes - what then is the difference in the tubes? Length, damping, or ???

 

Being that the Low is, well... lowered 1" I'd guess length,

but that's only a guess.

 

That should come with the different damper rod and cartridge. As I said, you can take a std height bike, install the profile low kit, and drop 1 inch. And yet - the numbers are different.