Rick.....
I have the Hospital G P/N with the 3 rows of bristles. I'll post pics tomorrow when I have recovered from............flying.
The regular P/N's have 2 rows of bristles but the Hospital G and commercial P/N's had 3. They were not successful as they put too much torque on the brush roll motor and it would burn out way too fast.
In terms of cleaning, I think it is wonderful! It really does fluff the napp and is the best performer of the P/N 1-2 nozzles IMHO.