Non-Automotive / Other

Dometic USA

R/F UNIV ONYX 21FT

$378.49

SKU: D018 R3314989NR.421

In Stock
In Stock
Ships by Jun 9
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

Designed with a shortened rear profile, the 400 Series reclaims valuable bathroom space while delivering 2X the front-load strength of leading competitors. Every model provides residential-style seating and quiet, soft-close comfort in a compact footprint. Built on a unified platform, the Dometic 400 Series enables seamless installations and unrestricted upgrades. Choose heavy-duty plastic or premium porcelain, round or elongated bowls—the 400, 410, and 420 share a universal footprint with a compact rear profile and 7–5/8" rough-in. With a standard 7–5/8" rough-in, universal 2-bolt mount, and tool-free seal replacement, the 400 Series is engineered for quick production installs to reduce service labor. Modular, tool-free parts reduce complexity to help streamline builds and warranty claims, while simplifying toilet upgrades and service for technicians and owners. Each model is tested to withstand 150,000 flush cycles and 2X competitor weight load capacity, reducing claims and ensuring reliability on the road. Assembled in the USA, the 400 Series delivers consistent quality, faster supply, and reliable performance. The Dometic Complete 411 delivers a smart balance of comfort, cleanability, and space efficiency. Its porcelain round bowl and shortened rear profile help OEMs reclaim valuable floor space, while the standard 7–5/8" rough-in and 2-bolt mount make installation and replacement easy. A 360° bowl rinse via foot pedal enhances cleaning with less water, and a sealed gravity system keeps odors in check.

Fitment

Fitment Guaranteed

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandDometic USA
Part NumberD018 R3314989NR.421

Videos

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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