These two paint boxes are tiny, light, and cute. The dimensions are 4-3/4" x 2-1/2". The lids are metal and the bases are plastic. I could fit in some half pans if I took out the brush holder, but these hold emergency paints, and I have half-pan palettes with better paints if I'm planning to paint away from home. One paint box contains watercolors, and the other contains gouache. There's also a Niji waterbrush and a Moleskine Cahier in my purse.
When these boxes were purchased, I though it would be an easy matter to take out the original watercolors. Ha! The original brushes had thick, plastic bristles, and that should have been a clue. It took hours to get rid of the original paints ... they were water-resistant! The top paint box is now filled with Yarka paints, and the bottom one is filled with cheap tube gouache.
Since the boxes are so small, they can be placed flat at the bottom of my purse, and I don't have to worry about wet colors shifting out of their containers.
At the bottom of this picture is an Altoids box which holds a pencil sharpener, kneaded rubber, and white eraser.
Of course, I've never used these supplies since I only have time to paint when at home, but I'm prepared in case of emergency.