A specially designed system of interconnecting foam media that allows you to customize for your hydroponic growing needs. Never outgrow your system, this engineered technology expands?with the maturing plant, positioning?each piece within the other to help minimize root disturbance. The fine cell structure promotes faster, stronger root growth with uniform moisture and drainage. The growing medium is wrapped and sealed in plastic helps reduce moisture loss. Transplant your blocks by simply cutting an X in the plastic on the slab that is the same size as the block and set the block on top of the slab medium.