Horticubes® XL is specifically developed for professional hydroponic growers. It is the first hydroponic medium to dramatically improve root penetration. The fully developed roots penetrate the bottom of the Horticubes® XL cube in just seven days and add an advantage of valuable control over your crop time. The specialized media density and fine cell structure promote faster, stronger root growth. A more vigorous root system means nutrients can be absorbed more efficiently, for stronger plants with faster growth. Horticubes® XL has been proven to boost both root growth and top growth of seedlings by up to 35% that can mean quicker, more successful transplants and significant time savings for growers with the capability to increase annual crop turns on plants like lettuce and herbs. Media maintains the original air porosity: the cells do not compact after continual watering. Sheets are pre-dibbled with seed holes (available in single or mutli seeded dibble sizes) for uniformity in depth and spacing. The sterile media arrives pathogen-free, to help reduce disease and insect problems. All Horticubes® media is manufactured in a “sheet” style, which fits easily into the industry’s standard “1020” trays. Each sheet is pre-scored for easy separation of a single cube, a block of cubes, or a strip of cubes. All Sheets below are top grooved except the 276 tray that is un-grooved. 162ct Sheet - 0.875" x 0.875" x 1.5"; Center hole 1.125" apart