RV bath basics
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Visit a local RV dealer and check out both "Wet Bath" and "Dry Bath". See if you can determine which yours is designed for.
A wet bath has a shower with toilet and sink in the same small space. Everything gets wet when you shower.
A dry bath has a shower stall. Sink and toilet are in the room, but not in the shower stall.
Sometimes the sink is outside the bathroom.
Search for "RV toilet"
Some toilets have a waste grinder and pump. Most drop directly into a black water tank directly under the toilet.
Search for "RV bathroom sink"
Search for "RV shower stall"
Dutchman Kodiak Cub KD176RD 2018
Nissan Pathfinder 2015