Kem Playing Cards - Pantheon Design (100% Cellulose Acetate Plastic Playing Cards) 100 % Plastic Kem Cards are widely regarded as the world's finest playing card. Kem cards are made entirely of cellulose acetate material, a durable plastic used in playing card production since the early 1900s. These cards are scuff and break resistant and completely washable. Set includes two decks and a convenient storage box. Available in Narrow Regular or Wide Jumbo size.