McDonald's 1993 The Flintstones "Tree-mendous" glass mug. These clear, textured glass mugs were a promotional item for the live-action The Flintstones movie released that year. Product Details: Collection: Part of a set of four unique "Bedrock" themed mugs offered by McDonald's, sometimes branded as "RocDonald's". Design: The mug features a heavy, textured glass design meant to resemble a tree trunk, with the handle shaped like a branch. Year: They were released as a limited-time offer in 1993.