This Windowsill Greenhouse Is A Reliable, High Performing Seed-starting Kit, Featuring Unique Double Tray Drainage Systems (black Growing Trays & Green Drip Trays) With Shatterproof Pvc Lids To Stabilise Temperature & Retain Moisture.the Windowsill Greenhouse Is A Reliable & High Performing Seed-starting Kit. It Features A Unique Double Tray Drainage System (including Black Growing Trays & A Green Drip Tray) Whilst The Shatterproof Pvc Lids Stabilises The Temperature & Retains Moisture To Encourage Quicker Germinationeach Windowsill Greehouse Measures 40cm X 23cm X 18cmeach Contains 5 Black Growing Trayseach Growing Tray Has 6 Cellssold In Packs Of 2