Size Design for Planting: 15 grid round seedling pot tray for 4 inch round pots, the outer size is about 16.85 inches x 12.6 inches, each grid is 0.2 inch from the bottom after placing the pots, this space can increase the air permeability of the potting soil and prevent plant root rot, this size is suitable for starting a variety of plants, allowing for the use of space and resources Quality Material: the round nursery pots trays are made from plastic, ensuring they are thickened and resilient for long term use; This allows them to withstand various environmental conditions, making them suitable for both indoor and outdoor planting; Each tray can hold 15 pieces of 4 inches round seedling pots, it can not only be applied as an ordinary seedling tray for seedlings, but also can be applied to transport seedling pots Designed for 4 Inch Seedling Pots: specially designed for carrying seedlings, these 4 inch round seedling pot trays are good carriers for small seedling pots; The ventilation channel design can increase the air permeability of the seedling pots, and the tray has a drainage hole in each of the 4 corners so you don't have to worry about root rot or overwatering with automatic watering, you can water any one of them and the water can into all the other pots, thus watering those pots Versatile Planting Options: these 15 grid seedling trays are suitable for a wide range of plants, including flowers, vegetables, and herbs, their versatility makes them suitable for gardeners who enjoy experimenting with different types of seeds Package for Gardening: each package includes 12 round nursery pots trays, providing gardeners with multiple options for planting, this complete set is ideal for those looking to start a small garden or expand their existing collection, the several trays ready for use will simplify your planting process