I may be wrong... but i think you 2 are both talking about roof ladders... but different types.
In 2015 (maybe before on some models?) Voltages began appearing with roof ladders that... instead of the removable type that simply "plug in" to round mounts on the body, were permanently attached, and folded flat against the rig when not being used.
We tend to think of most items being the same on our rigs from year to year, but they sometimes change. This is why most of us find it helpful to include our year, make, and model rigs in our permanent signature lines here... along with our tow vehicle, toys, etc. Confusion sometimes still happens, but less often.
Just some random thoughts...
2013 VOLTAGE 3200 (EPIC I & II)
2014 Ford F-450 PLATINUM