I love to paint with acrylics but I have yet to master the art of watercolors. These water pens are just the ticket for me to learn this craft. The tubes are a soft vinyl that are easily squeezed with a little pressure to force the water down into the brush area. As you can see in my pictures the different sizes enable me to use different strokes, one for large areas, one for fine detailing and a medium for small areas. I was nervous about getting the paint on the brushes because I didn't want them to be stained but the nylon bristles cleaned up fine with a little water. I like that they have tip covers so the brush stays moist as I'm using them or even when I have to step away from the easel. Easily refilled and secure enough that the water doesn't leak out through the threaded part of the pen. These should prove to be fun to work with. There is also an handy clip on the cover.
I received this product at a discount in exchange for my honest and unbiased review.