These sturdy 11x22x2¾" khaki plastic trays will last for years and are strong enough to hold 50 2" soil blocks without strain. Good for windowsills because they have no drain holes. Will cradle all the plastic trays we carry, as well as most other standard 10x20 trays. Use with a dome to hold in heat and moisture. Store out of sunlight when not in use; will fade and weaken if left in direct sun over the summer.