25-Pack Nylon Solid Plastic Balls, 0.5In(12.7mm) PA Nylon Precision Bearing Ball for Bearings Repair DIY Crafts Models

Unfortunately I ordered these for use as a more visible water level indicator in a sight glass, but these won’t float on water. I had hopes as the listing said that they were used in a variety of industries including “buoyancy valves, liquid level indicators” without specifying what type of liquid they would work with for that application. But I do now know it’s not water, although I have no idea what liquid they might work with. Now that I’ve eliminated their use as a visible marker in a sight glass, I’ll have to see what other uses I can find for these perfectly round, very smooth surfaced nylon balls that roll all over the place if placed on an even slightly off-level surface. These are well made and I have no doubt that they’ll work well as low noise ball bearings – see the magnified picture below. They certainly look like they’ll make great ball bearings, so I took away 2 stars for the ‘liquid level indicators’ that the manufacturer M METERXITY listed that could be used for that they won’t do for me.

Exactly as described in quantity and size. I got the 12.7mm (0.5") size and they measure 12.7mm dead on. I do a lot of maker/3D printing projects and these will be just what I need for some custom bearings I'm working on. Uniform, smooth, nice and round.