Fairfield Industries 24S-WT is a 24” Watertight Square Manhole w/ Steel Frame & 10” Skirt & Bolt Down Diamond Plate Cover. Access Manholes are some of the most well-known products from Fairfield Industries. Manholes typically are installed at grade level and provide access to underground equipment. Fairfield Industries manufactures manholes in various sizes, shapes and multi-port series with watertight access and custom configurations.