VidaWool Rockwool Block 40 with Hole, 4 Inch x 4 Inch x 2.5 Inch - Case of 216VidaWool. Cultivate With Confidence VidaWool blocks provide the space and uniform water and nutrient distribution they need to continue thriving in their second stage of life. Equipped with a UV protection liner and Hydro Xtend water dispersion technology, VidaWool blocks are intelligently designed to deliver healthy, even root zones and consistent crop performance. Mineral wool growing media helps to give more steerability to the grower and