The Snap to Vent Master Connector Kit includes one 90° elbow connector one straight connector, 2-seal rings and 2-snap connectors as well as one 4 in. dia. by 8 ft. long aluminum flexible hose. The 90-elbow is patented with a quick connection with the hose. . Pre-assemble the hose to the 90-elbows with the snap connector, place the seal ring over the vent and push 90-elbow connector onto duct for a quick, air tight and easy install. If dryer is not against a wall use the extra piece of dryer vent tape to secure 90-onto dryer vent. For regular dryer vent cleaning maintenance, simply pull the connector off the dryer vent duct for access and push back on when complete. Designed for all 4 in. round dryer vent duct.