I use the FOLD-A-COVER G4 here. It is made of hard plastic and is lockable... It also provides great protection from weather and rain.
The FOLD-A-COVER opens up on both ends so you can have a tool box sitting under it just behind the truck rear window.
It also all folds back and stacks up just behind the rear truck window and this gives enough clearance to use the fifth wheel hookup. Just ensure your 5th wheel hitch does not go higher the sides of the truck bed.
The only draw back I have with mine is when I was hooked up to the fifth wheel it was a challenge to get into my tool box but not impossible. I could gain access by raising all the folds in the vertical position
Above photos from google search
I also keep my 2KW Honda Generator sitting secured in my truck bed. This worked out great support the fifth wheel when I was towing one. When unhooked everything becomes out-of-sight out-of-mind in regard to what is stored in the truck bed.
I have moved my FOLD-A_COVER to two trucks now...
It really works wonders with my POPUP trailer giving me lots more covered storage space. This is where my 2Kw Honda generator lives 24/7
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
K9PHT (Since 1957) 146.52M
2010 F150, 5.4,3:73 Gears,SCab
2008 Starcraft 14RT EU2000i GEN
2005 Flagstaff 8528RESS