I have this new bath drain. It comes with two optional tail pieces. One uses outer threads and a nylon washer. The other uses fine inner threads. The drain basket is threaded for either one.

Are there any pros and cons to the two tail pieces? The inner-threaded one seems more secure to me. Stronger, fewer parts.

How do I seal the inner threads? They are very fine, they cannot use Teflon tape. Should I use silicone lubricant? Pipe dope? Someone told me to use silicone caulk, but that doesn't sound right.

There is no guidance in the instructions. The basket and all its mounting parts is from one kit, and it's threaded both ways for flexibility. The two pipes are from another kit, and they are both provided ... for flexibility. So I have lots of flexibility but no wisdom.

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  • 3
    Don't take any plumbing advice from your "use silicone caulk" someone. Ever.
    – brhans
    Sep 9, 2022 at 13:12
  • @crip659 I see what you mean but in this specific drain, 1) where the inner threads end in the drain basket there is a lip, so if you look down from the top you cannot see the top of the tail piece and 2) it's a tub so when full we're worried about pressure more than flow. It's in all directions, not "down past the lip of the pipe" and with the teflon gasket you have two large mating surfaces, below and above the gasket, that can misalign and leak but with the threaded pipe if you know how to seal the thread well (I don't) and tighten it well it should I think last longer. Maybe. :)
    – jay613
    Sep 9, 2022 at 13:27

2 Answers 2


Personally, I'd choose the gasket, since it removes the threads from the leak path, and is harder to corrode into immobility than the tiny internal threaded bits - I've experienced some rotted out brass tailpieces and prefer plastic because of that, actually.

If you think you can't use teflon tape on fine threads, you are not pulling hard enough (it stretches and gets quite thin and conformable), but use pipe dope anyway if you choose that one.


Each has its pro and cons.

I personally prefer the gasket, if you ever have to open it.

Since it is a drain line there is no pressure and limited possibility to leaking if installed properly.

The gasket one has a very short nut, so susceptible to tilting, not having a strong hold (be precise and gentle).

The threaded one has very fine tread, and you will not know till it leaks if you sealed it. Teflon should work, it can be stretched very thin, but that can result in no seal. However, you can remove it without additional tools.

  • 1
    I don't think that's an "air vent". Those holes in the drain basket are to allow the sink overflow drain hole(s) to run water down the drain instead of onto the floor.
    – FreeMan
    Sep 9, 2022 at 12:50
  • Correct, the holes are for the overflow. The drain will be held to the tub by the typical rubber gasket and metal nut that rest below those holes. The "short nut, susceptible ...." bothers me. I think the threaded one will be stronger and resist leaking if minor movement is encountered over time.
    – jay613
    Sep 9, 2022 at 13:37
  • I only have experience with sink tailpieces, not tub ones. In my experience the gaskets supplied with tailpieces are often not the best quality (like nylon - saving costs). Since the seal is made by compressing the gasket between the outflow and the tailpiece end, it's important that the gasket be both flexible and resilient over time. I've purchased the red silicone rubber aftermarket gaskets for both repairs and new installs and they've been great.
    – Armand
    Sep 15, 2022 at 20:33
  • Re: " The "short nut, susceptible ...." bothers me" I agree - is it possible to get yet another choice, with gasket but deeper threaded section?
    – Armand
    Sep 15, 2022 at 20:36

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