Determine your size for RV sinks
The regular p-trap for Recreation Vehicles has a 2 inches water seal when the vehicle is in the horizontal position or parked. When the vehicle drives up on the hill, the water seal will decrease to under 2 inches or will be zero depending on the hill. For people who drive mostly on the hills it is recommended to use a deep seal p-trap. The deep seal flex p-trap can be used to easily replace the existing one, because the Flex p-trap it is flexible. We have two sizes: 3 inches deep seal and 4 inches deep seal, depending of the space under the sink. You can buy any size that you need (plus or minus 1-3 inches) with a special order, and the same price.
RV double sink
(deep seal p-trap)
On hill In parking
A=45 degree A=0
Sh= water seal S =water seal
Sh=min 2 inches S=Sh=3-4 inches