Thetford 34120

Waste Ball Seal

Thetford 34120 is the waste ball seal for the Aqua-Magic Style Plus. The waste ball seal for the Aqua-Magic Style Plus. Same job as the Style II seal, different part.

Which models this fits

  • Aqua-Magic Style Plus

    Verified against Thetford Parts List, Aqua-Magic Style Plus (Rev E).

What this does NOT fit

Aqua-Magic Style II. Thetford’s Style II parts list assigns 42141, not 34120. Retailer listings claiming both are not supported by Thetford’s documentation.

Commonly confused with this

  • 42141

    42141 is the Style II and Residence seal. If your toilet is a Style II, 34120 is the wrong part.

How to tell which one you have

Check the model sticker. The Style Plus parts list also shows a shroud and shroud O-rings, which the Style II list does not, so a visible shroud around the base is a useful secondary clue.

Is this part still current?

Yes. Thetford still lists 34120 on its current parts list dated 11/4/2025.

Where to get this part

  • Check price on AmazonSold by Amazon

    This listing’s title says it fits the Style Plus and the Style II. Thetford’s own parts lists give the Style II a different seal, 42141. The part is right for a Style Plus. Do not use it for a Style II on the strength of that title.

    We earn a small commission if you buy through this link. It costs you nothing extra.

Check this before you order

  • Confirm the model sticker reads Style Plus.
  • If it reads Style II or Residence, you need 42141 instead.

Before you start the job

Wear gloves and eye protection, and disinfect tools afterwards, as Thetford instructs for waste-contact work.

Where our information comes from

We work from the manufacturer’s own documents. We have not installed this part and we do not test parts in a shop.

Last checked 2026-08-24.