COMC (Check Out My Cards) is the largest consignment marketplace for sports cards and trading cards in the world, founded in 2007 and based in Redmond, Washington. The platform hosts millions of individual cards from sellers worldwide, offering a centralized marketplace where collectors can buy and sell baseball, football, basketball, hockey, soccer, and non-sport trading cards. COMC's unique model involves sellers shipping their cards to COMC's warehouse, where items are scanned, cataloged, and stored until sold, streamlining the buying process by allowing collectors to combine purchases from multiple sellers into a single shipment. The platform's comprehensive grading integration, detailed search filters, and competitive pricing make it an essential destination for serious card collectors.