I bought something similar that was marketed like this:

> “Rhinomed Mute” Snore Stopper Nasal Dilator for Snore Reduction

This happens to be the exact one I tried. I'll probably try others in case there's one which happens to work better or be more comfortable (irritation of the nostrils at first was a real factor, took about a week to adjust), but with a hydrogen peroxide bath every few days they can last an arbitrarily long amount of time, so I haven't felt the need.