SMART Flow Elbow is a radius forming brace, also known as a durable elbow support designed to form flexible duct into highly efficient 90° elbows. It greatly improves air flow resulting in improved system performance and lower energy costs. It is an easier, quicker, more affordable alternative to the galvanized metal elbow commonly used today. It also meets independent standards for flexible duct use: The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), the American Institute of Architects, and the U.S. Green Building Council all recommend that a flexible duct used as an elbow should be installed with a durable elbow support. The Air Diffusion Council (ADC) recommends that the flexible duct bend radius must not be less than one duct diameter. Use precision engineered SMART Flow Elbows to maximize system performance.