The 501015-0270 PTFE-Teflon® Flange Insulator is designed for use with NW40 size ISO-KF flanges with 1.5 inches vacuum tubing on one side and a hose or bellow tubing on the other side. These tubes are clamped together with either model 100312905 ISO-KF wing nut flange clamp or 100318805 toggle clamp. Series 49UL flange insulators keep heat from escaping at flange connections for better temperature uniformity in vacuum piping applications. PTFE-Teflon® constructed heater jackets can be used in all critical applications where minimal outgassing, ultra-low particle generation, elevated temperatures up to 200°C, and ease of installation are required. These patented heaters are constructed with fully squared ends and a form fit shape to maximize thermal efficiency and temperature uniformity, minimizing thermal losses and power consumption.