Excellent for use as a stirrer in paint bottles. I use them for hobby model paints like Citadel, Vallejo and P3. They easily fit through the narrow opening of Vallejo dropper bottles. Bearings are heavy enough that a few jolts can easily dislodge the bearings from clumps of paint in the bottle, eliminating the need to tap paint bottles. The most important thing: NO RUST. I've soaked a few of these in alcohol and water for a few days and there wasn't a spot of rust to be seen.