White nylon plastic with a matte finish and slight grainy feel.
About this Product
Three different solids of constant width 3cm. These are hollow and have internal stiffeners. Each is a solid of revolution from a different plane curve. You get a very rounded Reuleaux triangle, a rounded Reuleaux pentagon, and a Reuleaux heptagon. All of them have width 3 cm in any direction.
See this link for these 3 models sold separately.