When sourcing fire wraps (also known as firestop wraps or intumescent wraps), you must prioritize the Fire Resistance Rating (FRR), typically ranging from 1 to 4 hours. Ensure the material is made of high-quality intumescent graphite or ceramic fiber that expands significantly when exposed to heat. For plumbing and HVAC applications, verify the expansion ratio (ideally 15:1 or higher) to ensure it effectively seals gaps left by melted plastic pipes. Additionally, check for moisture resistance and UV stability if the wrap will be used in semi-exposed environments.