This electric heated propagator base is the perfect size to sit on a windowsill featuring carbon fibre heating elements for non thermostat controlled even heat distribution includes 3 of the small high dome propagators made from high quality plastic these seed trays have clear covers with an adjustable dial vent to control the temperature and humidity the seed trays feature 2 tier cell drainage holes r perfect size to sit on a windowsillr featuring carbon fibre heating elements for e