VK4-H-8-1 Noritz Stainless Steel Single-Wall, Horizontal Termination Vent Kit The VK4-H-8-1 stainless steel horizontal vent kit comes with all the necessities to complete a horizontally terminating ventilation system. With a 4.1"-7.4" range in wall thickness capabilities, the kit is not only versatile, but easy to install and maintains a lasting professional appearance. As part of the N-Vent series, this product is UL approved category III venting, known for easy installation and forming tight seals. Horizontal Termination: When installing your tankless water heater close to an exterior wall and on the first floor, it makes sense to intake and exhaust air to the nearest place possible. Horizontal terminations are easy to install, and these kits come with a hooded termination piece to terminate your system with a professional look and protect it from moisture. Noritz N-Vent is approved for tankless and boiler stainless steel exhaust installations, enabling you to know you've made the right choice in both form and function.High temperature rated stainless steelHorizontal applications onlyFor walls 4.1"-7.4" thickEasy installation with a professional finishIncludes wall thimble with built in hood termination