Cave diving line markers

Because of the difference between the kinds of markers (the arrow shaped one has one with a dent and one with a hill, the round one has one or two bumps). Because of these it's easy to feel wich marker is yours when cave diving.

I printed these in PETG because of the stronger UV resistance and being more strong all around. The filament I used was glow in the dark, it's not tested yet if this helps while diving.