These do NOT stack!!! The 1oz ColorCase does stack; however, the .5 oz does not--very unstable.
The Scrapbook.com metallic pigment (gold & frost) reinkers do NOT fit in the .5 oz ColorCase. Other Scrapbook.com reinkers do.
Good quality plastic. Looks nice when filled; however, they take up a fair amount of space--because they can not be stacked!