I am not totally sure if escape hatches are rated differently, but the standard roof crank up vents are sized by the rough opening in the camper roof. Meaning a 14" x 14" standard crank up roof vent fits in a 14 1/4" x 14 1/4" rough opening.
If you take the ceiling garnish down inside the camper, you should be able to measure the rough opening in the roof. Then get the escape hatch that shows the dimensions that will fit in that rough opening.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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