Hi, I am new to the forum and the world of 3D printing.

I have a simple product that I want to create but it needs to have certain properties:
-I would like it to easily float in water, even carrying an additional objects weight. I also thought about printing a void so an air chamber would add the buoyancy. I will have to experiment with the objects weight and the buoyancy of the material
-It must be flexible with the ability to stretch similar to an o-ring. This item will be fit over different shaped "stems"
-It must be able to be shaped and stretched many times without damage and the ability to return to its original shape
-It must not be affected by UV and water

After doing some initial research, it appears TPU or TPE might be close to what I am looking for. I have no idea on the buoyancy however.

I am completely new to this and do not own any 3D printing products but am anxious to learn and experiment.

Thank you very much for the help!