Replacement Toilet Seat For A Dometic Masterflush 7640
Updated 08/18/2025 | Published 07/11/2025
Products Featured in This Question
Question:
Does this seat fit the Dometic 7640 masterflush toilet? Dometic 385343829.
asked by: Rosie B
Expert Reply:
Hi Rosie!
I did some research and it looks like the Masterflush 7640 will use the same toilet seat as the 310 series, not the 500 series you found. So with that said, you will want to choose one of the following:
Dometic Replacement Wooden Toilet Seat with Slow Close Lid for Dometic Part-Timer RV Toilets - White # DOM83FR
Dometic Replacement Wooden Toilet Seat with Slow Close Lid for Dometic Part-Timer RV Toilets - Tan # DOM23FR
Both include all parts needed for the install and they are color matched as well.
What do you have this toilet installed in?
(click to enlarge)
Rosemary B.
8/15/2025
I’m not sure why my response didn’t show up, but I’ll try again. We purchased Dometic 385343829 cover and seat and it fit perfectly. It’s a heavy wood item in white and we’re very happy with the quality. The only modification we had to make was to cut off the mounting bolt tabs and then the vacuum breaker cover fit over the bolts.
Lazer S.
8/18/2025
Product Page this Question was Asked From
Replacement Wooden Toilet Seat and Lid for Dometic Full-Timer RV and Sealand Toilets - White
- Accessories and Parts
- RV Toilets
- Toilet Seats
- Dometic
more information >
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Lazer S.
8/7/2025
Hey Rosie, Did you end up choosing one of the suggested toilet seats for your Masterflush 7640? I'm curious to know if it worked out for you, as it could really help others in a similar situation. Let me know how it went!