The Allegro Manhole Ventilation Passthru (MVP) (Patent Pending) is designed to
maintain and re-direct air flow with minimal restrictions into manholes, sewers and tanks. The Allegro MVP is the first manhole system that combines three components: a low profile air vent, 90° elbow and built-in mounting–
all in one unit.  Once placed into the manhole, the elbow fits underneath the lower cross bar on the guardrail.
The MVP is stabilized by placing the manhole cover onto one of the flat channel corners.

This unit comes with a, collapsible duct stored in a small storage bag that can be dropped down into the manhole
with a quick release of the drawstring. The duct is collapsible, but springs back into shape once the worker is
through the opening and down into the manhole. The ducting is vinyl and polyester with PVC coating and heat resistant up to 180°F.

The MVP is lightweight at 11 lbs., and made of bright yellow, recyclable, low density, high impact polyethylene to withstand heavy use and temperature extremes.  The complete unit is a low profile assembly, easy to store and transport and ships in one small carton.