1440 Cells Seedling Starter Trays for Seed Germination +10 Plant Labels (240, 6-cell Trays) Twenty 10"x20" 'flats', contains 1440 cells, (will ship as 'half flats' for best shipping cost). Each cell measures 1.5" square by 2.25" deep. Ideal cell size to transmit room temperatures for optimal root growth. Includes 10 plastic plant labels! (5" long). Drain holes at bottom of each cell.