Extra room to mixing and storing thinned paint. Handy markings make measuring and mixing a breeze. Caps screw on snug and seal very well.

I bought this to put some thinner in it to clean my brushes and it works good

This is basically an empty, taller version of the 23ml Tamiya paint jar. The cap is an opaque white made of plastic while the rest is made of glass, so unless you store the jars upside down, you can hold strong stuff like Turpentine without worry of it coming through the jar. I use these for storing filters I make myself and it serves that purpose very well. At $1.70 this will eventually pay for itself in paint that doesn't get wasted.