Wiss WF18 18-Inch - HVAC Metal Folding Tool Go to amazon.com Related posts Which is the best metal forming tools? FeatureIdeal for folding channels and making longer uniform foldsFold 3/8-Inch and 1-Inch depthsSight holes to help assure proper depth alignment DescriptionDescription: Wiss 18-Inch Folding Tool Folding Channel Depths:-3/8-Inch and 1-Inch.