1. Water valve threads are recessed back from the end of the fitting so a normal depth FIP connector only engages few threads
2. Threads are very soft
3. 94ish RV with a grey plastic FIP water connection
4. Tight spot
5. Water valve threads stripped
I was able to cut off the end of the valve threads and connect to what was left.
Also bought a spare valve and the threads are not recessed as far New Durable Plastic Water Valve Kit 385311641 for 300 310 320 series - for Sealand marine toilet replacement
Knowing what I now know I would have bought a flex connector with one extended FIP connector like BrassCraft PSB145 Speedi Plumb Flexible Vinyl Water Connector for Faucet
and connected the water before bolting down the toilet.

I took out the original model #300 because it made plastic squeaky noises and the seat is not replaceable. It was all plastic and worked ok, but this one is a definite step up, no squeeks Installed in minutes and the porcelain bowl has holes that direct the water around the bowl in a circular action that wets the whole bowl evenly. I'm sure the china bowl will clean up better and last longer too...Dometic makes a great product.

I'm on my second one. The flush mechanism is all plastic and tends to break in all sorts of ways. Every time it would stop opening the ball valve I'd take it apart and find 2-3 new chewed up pieces of plastic that broke off from various places. I kept doing makeshift repairs on my original 310 until I finally gave up and replaced the whole thing since there are no internal parts available and, unfortunately, I couldn't find a better option. I've had a Thetford toilet before and, although better in some ways, it had its own unique issues.

Here's what I've learned to prolong the life:
1) Place an adhesive doorstop/bumper on the floor where the flush lever would otherwise make contact (See attached pic). The somewhat faulty design permits the lever to over extend beyond the range of the ball valve. The plastic interface between the lever and ball valve wears overtime until the plastic nubs wear off and the valve will no longer be rotated by the lever. It also prevents excessive spring tension as the spring tends to break off the plastic ribs that hold it in place. This still permits complete opening of the ball valve. Pushing the pedal all the way to the floor only serves to flex all the plastic parts beyond their normal range of motion and load up the spring with more tension than necessary.

2) Run a bead of silicone around the joint between the plastic base and the ceramic bowl (see attached pic). As other reviews mentioned their plastic base became full of liquid over time. This happens when liquid gets outside of the bowl and runs down the outer surface of the toilet. It hits that seam and goes right into the void between the double walls of the plastic base to live there forever and stink. If you've got kids it'll be full of urine in no time. Seal the joint and it will just run down to the floor where you can clean it up at least.

3) Never use any kind of caustic cleaner in the bowl. It will make the ball valve seal become permanently sticky. That will apply more force to the aforementioned interface between the lever and ball valve, wearing the parts. Use caution when pouring in your tank chemicals to avoid getting it on the seal.

4) Get silicone plumbing grease and keep it near the toilet. Apply it to the seal after every trip to keep it supple and slick. This makes it seal better, keeping odors in the tank instead of in the RV, and also reduces wear on the lever mechanism. If the seal starts to stick even when lubricated, replace it immediately... it's a lot cheaper and easier to replace than the whole toilet due to lever failure. On this model you just jerk the seal out and push in a new one. No tools or disassembly required. When it starts to get hung up, replace it before it causes damage to the flimsy mechanism.

This toilet is perfectly broken. It fits well, connects well, works well and is the perfect replacement. Unfortunately Award Products was late to tell me that 9 out of 10 toilets they send out are broken so steer clear of this third party seller.

Had to replace the toilet on my aging rv. The toilet plumbing lacked a shut off valve in my coach. so after a trip to the hardware store I proceeded to replace the bare PEX hose connection and add a residential shark bite fitting. this is where thing got bit complicated(if you didn't read the manual first). See I installed a pre-crimped toilet hose ball valve connection to my water (PEX) line. here in lies to problem created by not reading. Residential Toilets are 3/4" NPT (for the most part). Water faucets for sinks are ½" NPT. guess what an rv uses....everywhere?!? yep a faucet connection. Beyond that, this is a very nice toilet. I opted for the sprayer (you know for those bathroom water fights you want win?). It's a great product and despite the size of the vacuum break fitting not coming with an adapter for residential connections it is still well worth the money.

Disclaimer: Don't try to have a water fight with the sprayer wand. You, or your victim, may catch something horrible and turn into a zombie. Or, you may just end up spending a lot more time on your new friend learning to pronounce the names of fun diseases and the doctors who treat them.

-Cheers