Polyurethane Foam;Share the luck with our 4-leaf clover stress ball, also know as the lucky; Our handcrafted polyurethane foam stress balls are a fun way to promote your company, organization, hospital or school, while also helping everyone who receives one squeeze away the stress of everyday life!; We offer hundreds of creative shapes to meet the needs of any promotional program!; Not intended as a child's or pet's toy; Product Size: 2.75" w x 1.5" d x 2.75" h ;