Spray foam is a two-component, closed cell, Class 1 fire-rated, spray-in-place, interior, polyurethane foam system with nominal core density 2.0 – 2.3 pcf. Ultra-Thane 205 HFO uses next-generation blowing-agent technology that provides climate change respectful, low global warming potential (GWP) performance, with superior per board foot yield. HFO technology spray foams have been adopted and required in many states.