Grodan Expert Slab, 6" x 3" x 36" - Case of 12Grodan Stonewool Gro Slabs Gro Slabs provide the final stage for growing a spectacularly large plant. Transplant your Gro Block plant onto a slab just like professional growers. They come in clearly marked biodegradable UV resistant sleeves for comfortable handling and algae prevention. With the Uni Slab, all plant roots are protected and contained for the life of the plant. Due to its size, the Uni Slab is perfect for one large plant. Uni Slab has