STRONG AND DURABLE – Built from ultra-tough, top-grade BPA-free white plastic HIGH REFLECTIVITY – The white plastic reflects light back to plants LARGE SIZE – With an outer dimension of 21.2" x 11" x 2.48", these trays are big enough for not just seed germination, but also seedling/small plant development NO DRAIN HOLES – These trays are watertight, which retains runoff and saves you time when caring for plants VERSATILE AND REUSABLE – Trays are multi-purpose and can be used in indoor gardening, greenhouses, for wheatgrass and microgreens cultivation, small hydroponics applications, and more COMPATIBLE – Fits perfectly with most 2", 4", and 7" tall humidity domes and seedling tray/plug inserts, as well as with all 10" x 20" seedling heat mats