The 50pcs Rockwool Cubes are made from molten rock spun into cotton candy-like fibers, making them perfect for rooting cuttings, starting seeds, and plant propagation. These cubes are predrilled with planting holes for easy seeding and transplanting. They are widely used in hydroponic systems and provide high water absorption and oxygen retention. Get faster initial rooting and effortlessly establish root systems with these rockwool grow cubes! Features 1. Made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. 2. Great for rooting cuttings clone plants, germination start seeds and more. Encourages faster initial rooting & its firmness is guaranteed. 3. Much easier than starting in soil! Predrilled planting holes make seeding and plant propagation a breeze. Great for hobby and commecial growers. 4. These rockwool starter plugs are widely used in hydroponic, seed starting, cuttings, plant propagation and so on. 5. Rockwool grow cubes keep the seeds long enough to establish a root system because of they have high water absorption while retain a lot of oxygen, cubes will not sepreate after immersion, easily transplant to net pots, soil, planting machine after rootted. Specification Material: Rock Wool Color: Green Size: 444cm / 1.61.61.6in Weight: 240g Package Include: 50 Rock Wool Blocks