We designed this system for season after season of successful seed-starting. The leak proof tray holds 24 individual cells, so you can bring the ready-to-transplant seedlings to the garden without disturbing seedlings that aren't quite big enough. Cells are tapered for easy seedling removal, and a wire grid in the base creates a built-in water reservoir. An all-natural jute mat acts as a wick, delivering consistent, slow moisture to roots – ensuring seedlings grow healthy and strong. Replacement jute mats available separately. Galvanized steel 12-5/8" L x 8-1/2" W x 2-5/8" H overall Each cell is 2" sq. at top, 1-5/8" sq. at bottom x 2-1/4" H Holds approx. 19 cups of soil Compostable jute mat is 8.5" W x 13" L x 0.15" H Gardener's Supply Exclusive