Imperial Mfg Group Usa Inc

imperial 4 in. metal worm gear clamp - Description

This Imperial 3-in to 4-in Aluminum Increaser allows you to connect pipe of different diameters where air flows from a smaller pipe into a larger pipe. Crimped on the large end, it increases the diameter of a 3-in round return or exhaust air pipe to 4-in, while maintaining optimal airflow. The increaser is ideal for general purpose venting applications and is quick and easy to install.