The 10”x10”x7” block from GROW!T Commercial Coco is the largest size in our lineup. With a full 3 gallons of premium coco coir, there is plenty of room for rooting. With its stable shape, this 10”x10”x7” block works well for mother plants and tall flowering plants. RapidRIZE blocks start off compressed for easy shipping and storage, but they expand fully in approximately 1 minute after saturation. All RapidRIZE blocks feature a wide, low-profile shape, to match the specific rooting pattern of your favorite herbaceous annual plants.