Steel Blue Square Corozo/Tagua "Five Squares Flat Pillow", 18mm / 11/16" # SK-522
Square button with four square holes. It's almost 1/8" thick but then slightly raised - 'pillowed' in the center. Steel blue-gray color. 11/16". Satin finish, very smooth with a slight shine. Sold per button.
Vegetable Ivory/Tagua/Corozo is made from a tropical nut. It's sustainable, strong and durable, machine washable/dryable, with a unique texture that is much nicer than plastic.