For home and market gardeners. Round cells. Use with Seedling Trays for extra support or with Leakproof Trays for bottom-watering. Holes spaced for canopy development. 38-cell flats are recommended for basil, cabbage family, peppers, other veggies, herbs, and flowers. Compatibility: Use with all Johnny's trays except Shallow Leakproof Trays (white) and Shallow Germination Trays (black).