Scubacastor
Contributor
In fact, the problem is not really the weight in air but the apparent weight in water. Loc-Line may also be consolidated by filling the interior of the tube with more rigid materials. Anyway, the answer seems to be definitely yes if you have a look at the bottom of the second page of this linked document:
http://www.gateshousings.com/docs/feature sheets/PC Housing R5 10-5-04.pdf
http://www.gateshousings.com/docs/feature sheets/PC Housing R5 10-5-04.pdf