Sedum cassettes of high quality for green roofs or sedum roofs absorb CO2 from air pollution and isolate and cool buildings and houses.+ Size: 45x50cm+ 4.4 pieces per m2+ Quantity per 29 pieces, suitable for 6,46m2+ 6 to 8 different types of high quality sedum+ Easy to mount by click system+ Suitable for flat roof or slightly inclined max 15 degrees+ Energy saving+ Insulating+ Cooling on hot days+ Absorbs CO2 and filters air pollution+ Put root cloth under the trays first is recommended