12 Cell Seed Starting Set - Tray, Insert, DomeSeed Starter Combo Tray Includes: Drip Tray, 12 Cell Tray Insert & Humidity Dome. The the complete growing tray set for seed starts. The drip tray has no drain holes, and the 12 cell insert that nests within the drip tray does have drain holes for water regulation, and watering from the bottom. The clear humidity dome fits snugly. 12 Cell Seed Starting Set Tray, Insert, Dome With care, these seed starter combos can be reused several times. Disinfect