Roto-molded septic tank lids from RotoSolutions are manufactured out of lightweight and durable materials for easy handling and transport. They are sold with hardware kits that include stainless steel components. The lids are sold in boxes of six and are made to fit 12-, 18- or 24-inch I.D. corrugated pipe. They can be used with or without the sand-filled option. They are easy to ship and install. 800/868-0973; www.rotosolutions.com.