I don't have a copy installed here at work, but if I recall, the L is the min value, H is the max value. I looked at the ones in the standard screen, they were something like STDL10H250 with the standard DRO string added on at the end. I found that if I removed the D (I think), It would not display the numbers with the slider. I didn't need them since I had a DRO displaying them. I wanted to make a horizontal slider, and Art said it was possible, but the info he gave didn't appear to be correct.
If there is any info out there, I couldn't find it.