White sealant used by factories

If you are talking about the stuff under items attached to the exterior it is usually butyl tape. It is very durable and can be purchased at any RV supply/parts place in varying widths. On rubber roofs Dicor self leveling sealant is king.

I am planning on caulking the seams of my fiberglass roofed/sided TT using Loctite polyseam sealer, all purpose caulk, clear. the owner's manual sez to use a urethane caulk. If I had a rubber roof I would probably slop on some dicor.
bumpy

JRS & B wrote:
I thought Dicor was "self leveling" and mainly used for flat surfaces because of this trait. .

There are a number of different Docor sealants. One is self-leveling for horizontal surfaces, other for walls and vertical seams, ect.

I thought Dicor was "self leveling" and mainly used for flat surfaces because of this trait. Proflex was used when the rubber around all of my slide outs rotted in the Florida sun and had to be replaced. Profelx formed a nice small bead, set up quickly and adhered nicely.

Guess you don't do much reading on the forums? Silicone is probably the WORST thing you could have used. Hopefully it was cold enough that it never stuck to the body. Downtheroad gave you the best answer. Although I tried Proflex once. Worst experience I have had in a really long time. The stuff sagged, took for ever to cleanup and never really stuck.

Not sure exactly what you are asking...but if you are asking about what caulk/sealant to use....probably Dicor or ProFlex.
Available on line or at any RV outfit that has a parts department or shop.

Do not use Silicone.