Designed to fit 20mm diameter tubes; 24 tube capacity (tubes not included). Great for storage, transport and organization; Each holder has 24 holes (20mm diameter each). Made from lightweight yet durable high density waterproof, non-scratching, anti-rattle, black foam material. Note: Avoid halogens, strong oxidizing agents, benzene, petroleum ether, aromatic and chlorinated hydrocarbons. Easy to clean (can be washed and rinsed, top rack dishwasher safe). Measures approximately 6.75" x 6.75" x 3".