Allegro 9650 20 in Diameter Ducting 15 ft Length

Ventilation Duct for Manhole Blowers

This Allegro ducting is built for confined-space ventilation, connecting to blowers used in manhole applications. The 20 inch diameter matches the blower outlet so airflow moves without restriction. Workers who need a straight, flexible run between the blower and the entry point will find the 15 foot length convenient. It is not suited for permanent HVAC installations that require insulated or fire-rated duct.

Vinyl and Polyester with PVC Coating

The vinyl and polyester construction with a PVC coating resists moisture and abrasion from rough concrete edges. Flexible duct of this type cannot support itself across long spans, so it must be laid out or suspended to avoid kinks that reduce flow. The material handles the temperatures typical of blower exhaust but is not rated for high-heat industrial fumes. Buyers needing insulated or UL-listed duct for code compliance should look elsewhere.

Black and Yellow Colour Coding

The black and yellow colour scheme makes the duct visible in low-light manholes, reducing trip hazards around the hose. At 15 feet the coil is manageable for one person to carry and deploy without a reel. No cuffs, clamps or couplers are included, so installers must supply their own connection hardware. Teams that require quick-connect fittings or integrated hanging loops will need a different product.