If this is an emergency exit window, then it is hinged. There are gaskets that seal the "inner" part of the window that swings out to the "outer" frame that holds the window in place to the trailer. These gaskets wear out and can be replaced with a "D" shaped gasket/seal 1/2"X3/8" should work. You can check this out (if it is an fire escape window) buy flipping up the emergency handles and swinging up the window.
1999 28' Safari
2012 F150 Platinum Max Tow 7650 GVWR 3.73 Elec. Locking Diff.(Prev 2003 Dmax).
Honda EU2000i, Equalizer Hitch
AM Solar Panels 150W - 2 Trojan T 105 6V Batteries
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