R454B is a hydrofluoroolefin (HFO) and hydrofluorocarbon (HFC) refrigerant blend, primarily used as a low global warming potential (GWP) alternative to R410A in residential and commercial air conditioning systems. It consists of two components: R32 and R1234yf. R454B offers a significantly lower GWP than R410A while providing similar cooling capacity and energy efficiency. It operates at similar pressure levels, making it a suitable replacement with minimal system modifications. R454B is mildly flammable (classified as A2L), so it requires careful handling and appropriate safety precautions. Its lower environmental impact and efficiency make it an attractive choice for new systems and retrofits.