Abstract: A hand tool combination of a knife having a double edged blade for piercing and cutting duct insulation and a wire cutter swingably engaged with the knife for cutting wire embedded in the duct insulation. The hand tool includes two jaws. One jaw forms the double edged blade and includes an anvil. The other jaw includes a wire cutting edge. The jaws are drawn together to operate the wire cutter by squeezing handles engaged with the jaws. The handles are also manipulated to operate the blade.

Abstract: A blade for cutting a groove in ductboard and forming a corresponding scrap strip of ductboard. The blade includes two blade portions depending from a support member such as a hand tool with a sled for engaging the ductboard. Each of the blade portions includes an inner end which engages the other inner end to partially fix the blades relative to each other and partially restrict the blades from spreading which may be caused by the horizontal grain of ductboard.

Abstract: The present invention is a tensioning and cut off tool for applying a strap having a locking collar and a free end to a bundle. It features a quick release operating mechanism that cuts the strap with a snap action in response to a certain level of tension that has been applied to the strap by the tool. It also features a resetting means for resetting the tool after the cutting action to a position where the tool can be used again. It further features a non-tension responsive cutting mechanism so that either the quick release tension related operating mechanism or the non-tension related mechanism may be selected to cut the strap.