calvana (2 pack) calvana 4” plastic round drainage grate cover, fits 4” pipes, prevents debris, ideal for lawns, patios, and walkways, durable uv-resistant plastic, easy installation, green is up for auction in Patio, Lawn & Garden. The current bid is $1.00, 93% below the $14.99 MSRP, in Good Condition. This auction has ended — similar items appear in live auctions regularly.