Ridgid 36092 Model 405/408M 8mm / 5/16" Lever Instrument Bender is a dual-purpose product being both inch and metric. The 90-degree set up generates the leverage required to produce smoothdistortion-free bends to 180 degree in soft coppersteeland stainless steel tubing. The open-side design slides over tubing at any point. This bender is clearly marked in 15 degree increments. Throat Tube O.D. 5/16" and 8 mm.