Bottomless Bath Bathtub Overflow Drain Cover
What this bathtub overflow drain cover does is simple: It seals the overflow drain in your bathtub via 12 small suction cups around the edge, allowing the water to fill up a few more inches. I prefer showers over baths most of the time, but when I do want a bath, I like being able to totally submerge myself, including my head. This makes that easier.
If you’re concerned about overfilling the bath, it’s not a 100% solid seal; a hole in the top of the cover helps keep the water quantity under control. Just don’t go run a marathon or something while the bath’s filling and you’ll be fine.
Get it for $9 on Amazon.