The plastic seedling trays are designed for preparing your seedlings in paper chain cells.
With the 2 J shaped Spreader rods, open your paperpot paper chain cells on the trays and hold them in place using the tray or depression spreader.
The next step is to fill the cells with soil or compost before sowing with the seeder plate.
When the seedlings have grown and are ready for transplanting, use your Paperpot transplanter.
The plastic tray has holes so that the water can drain out naturally, allowing the roots to breathe.