1.5" Grodan Rockwool Cubes for Seed Starter (98 Hydroponic Plugs) + The Hydroponic City Stakes ALR Industries After producing millions of gallons KWANWA After producing millions of gallons of organic bio fertilizers for some of the largest USDA certified organic farmers in the country for over a decade 1 velcro commuter strap on the front + 1 longer commuter strap on the upper bottom( the long strap can fixed the bag on the head tube firmly) + 1 commuter strap on the lower bottom The V shape design of the plug discourages tangling of roots between the plugs in the A OK plug sheet Seedlings started in cubes are easily transferred to blocks and then onto slabs