For blocks of rockwool and other grow media. These Grower's Edge® Block Covers blocks light from media- reducing algae and pest problems. Use white side up to reflect light. Use toothpick to hold cover in place. Hole in center of cover measures 1/2 inch in diameter.
Item Number: 138122
Universal Product Code: 870883008376
Manufacturer: Sunlight Supply
Manufacturer's Part Number: 714820
Brand: Grower's Edge