The Suburban Water Heater Access Door is designed to fit the ST-42 (5381A) and ST-60 (5382A) On-Demand Water Heaters. This exterior door is made of corrosion-resistant steel that's finished with tough baked-on enamel to provide extra resistance to chipping. Door is easy to install. Tough baked-on enamel finish for extra resistance to chipping Easy installation | Suburban Black Door For ST-42 & ST-60 Tankless Water Heaters