Red Square 9/16" Corozo/Tagua "Five Squares Flat Pillow", # SK-518
Square button with four square holes. It's almost 1/8" thick and slightly raised - 'pillowed' in the center, on the front side. 9/16". It's lightweight yet very strong, with a slight sheen but not plasticky-looking. Sold per button.
Tagua is sustainable and beautiful, carved from a South American nut. It's durable, washable and dryable (but not with too much heat.)