1. Compatibility: 385311652 rv toilet seal and 385311658 rv toilet flush ball seal are designed to perfectly replace dometic 300, 310 and 320 series toilets. They do not fit models: 210, 510 or other models not mentioned. Please confirm that the rv toilet replacement seal is suitable for your toilet before purchase. 2. Applicable Scenarios: The rv toilet gasket and rv flush ball seal can effectively deal with the problem of odor and water leakage caused by the rupture of the original toilet seal. They can keep the air in the RV clean, save your precious time and improve the quality of life. 3. Premium materials: Our rv toilet seal kit is made of special rubber, so it has a long life. Our factory uses original devices to make molds, making the gasket fit perfectly. It will help you fix your problem and keep water in place. 4. Easy to Install: It only takes you a few minutes to install. First, turn off the water supply, just pop the old seal out (no disassembly of the toilet is required) and put the flush ball seal in place, ensuring it is seated fully. Finally, secure the toilet using the provided brass bolts, nuts and bolt caps. Note that the marked side is facing up. Check for leaks, and the job is done.