The Hollandia, Electric Heated Propagator is an ideal size to sit on your windowsill. The individual propagators sit on a tray to allow an even heat distribution from the non thermostat controlled heat mat, giving an approx. temperature of 16 - 19 deg. The high quality Hollandia propagator lids include an adjustable vent to control humidity. The Hollandia heated 3-Bay Windowsill Propagator includes a capillary mat and tray, the reservoir will hold 1.4 litres of water for a constant supply of moisture taking away the need to water daily.