Profile: Doby Verrolec is a manufacturer of ductwork jointing systems. We also manufacture bespoke metal sections and roller shutter doors. We supply a full range of slip-on duct joint accessories to suit all sizes of duct flanges including corner pieces, clamps, and gaskets. Our ductwork stiffener is fitted to the outside of ductwork between the cross joints to strengthen and stiffen the ductwork, whilst also reducing vibration. Fixing centers are rolled into the stiffener during manufacture. This ensures an easier and quicker fitting time by drilling stiffener and ductwork for fasteners in a single operation. Our duct access doors are designed to provide inexpensive trouble free access to fire and volume control dampers & associated ventilation equipment mounted within ductwork.