flexible connector at equipment: enough slack, no collapse equipment connections: rtu, ahu, vav, fans & louvers flexible duct connector canvas vibration isolation fan ahu slack install the approved flexible connector straight, sealed, supported, and loose enough to isolate movement without sagging into the airflow. a bad flexible connector leaks, tears, transmits vibration, and can choke the equipment opening. equipment submittal, flexible-connector manufacturer instructions, vibration-control detail is this flexible connector aligned and loose enough for isolation without sagging or carrying duct weight?