ULTIM8 is exactly correct...the
Bathmate sticker should be used as a reference-point vs. an actual length. I experimented on both my X40 and Goliath models by sealing them on my kitchen counter and using The VacuVin to compress the gaiter fully...then I used an actual tape measure to compare it against The BM gauge. Both were showing 3/8" more than the real measurement, so I usually subtract 1/2" from what I see in the
cylinder during my sessions.
I don't think my BPEL and my PBPEL would be much different, but my MSEG and PMSEG definitely is.
This is a good thing to keep-in-mind during your training (I'm thinking
Bathmate knew what they were doing when placing that sticker, lol)