That explains why Dave raised his price.

What is better, domed or flat? The vents I got with my Lehigh plug are flat.

That cause you got them from me. Those are prototypes that never went to the market. The domed is a little better, and when you purchase more that's what you'll get from Lehigh. You won't need any for 5 years I bet. I think I sent you two.

Oh okay. I just found a couple other flat ones here I had for another plug so I'm good for ten years. Lol.

Lol, you should be.

Do you have to clean out these vent liners every so often or do you just replace them?
If you do have to clean them out, could you instruct how?

You should never have to place any kind of object in the flash hole of the vent liner you do have to soak the Vent Liner to help get it clean. I use a tooth pick on the input end of the vent liner to help remove the residue but nothing goes through it.

A Vent Liner wears out when the flash hole erodes due to gas cutting. The Flash Hole can be checked every few hundred shots with a pin gauge to measure erosion.

I'm learning this stuff too on the vent liners...Once you remove the liner, for cleaning, you do want to clean out the threads where the liner is screwed into the plug am I correct?

Obviously when you do clean the breech plug you gotta take the the vent liner out to drill out the plug. I wipe the outside and the threads off and replace back in breech plug. It's pretty simple and fast.