Hydrofarm CK64001 Humidity Dome A heavy-duty plastic dome Fits on 10-inch by 20-inch tray It will help retain moisture and heat to improve germination of seedlings Three adjustable vents one on top and one on each end for perfect humidity and temperature control Dome measures 2-inch Humidity dome Made of heavy duty plastic dome Fits on 10-inch by 20-inch tray Provides warmth for faster growth Measures 12-inch in length by 2.5-inch in width by 2.3-inch in height