Here's what other sites are saying:
KUPILKA products are made of a Thermoplastic Natural Fiber Composite Biomaterial. It is made up of 50% pine fiber (wood) and 50% plastic.KUPILKA means "little cup". The word KUPILKA stems from the Finnish word for cup which is "Kuppi". It also refers to a term used by Finnish people decades ago, when men and women warmed up their hands with their "Kuppilka" or "little cup" by drinking hot beverages during the rough Finnish winter.