This plastic palette, based perhaps on the brass paint box, is a great design. I've been using the half pan version as my sketching palette for about 6 years (as of November 2019). I use the full pan version for my gouache travel palette of full pans. It is from jacksons in the UK. Here is an affiliate link to both versions.
While it is a bit more expensive than some of the other folding palettes, it is so versatile that I have made up a few different versions for my students. I rather like having all the colours in one section so they don't spill into each other when the palette is shut. This also has very deep mixing areas. It is light and strong and big enough to use in the studio but light enough to take into the great outdoors. The catch is very secure and there is a video showing how to open it!
Here is the half pan option. You can use half pans and change your colours around, or put the watercolour directly into the wells. Standard half pans fit in snugly without rattling about.
|Frank Herring : Compact Palette Half Pan : 26x13cm Open 13x8cm Closed|
Here is the full pan version, designed to take 12 full pans. Each pan section will actually fit two half pans if you sand them down a little so it is also very versatile.
|Frank Herring : Compact Palette Whole Pan : 26x13cm Open 13x8cm Closed|
Here are some options - the first is the full pan version with half pans added into some of the the spaces. The second is the half pan option with 8 additional half pans added into the brush section - great if you want to hold it for plein air. The third is the half pan option with the thumb hole filled in and extra half pans added to the space. This is my current plein-air palette. Note that a compact water brush fits in well.
The pans can be glued in but I prefer to use blu-tac so they can come out again! Or fill the paint directly into the palette without using half pans if you are sure you won't want to change your colours around!
This is another configuration - designed to have just 8 colours around the outside, with the space to mix other colours in the added half pans. Just a little sanding with fine sandpaper allows two half pans to fit in the whole pan wells, though the Schmincke half pans fit without sanding. The paint was squeezed directly into the full pan well holes though whole pans could be used for ease of changing them.
I really recommend this palette option for sketching or plein air. I've been very happy with it.
You can see a number of other palette suggestions, including more configurations of this one, on my website here.