KAKA Industrial RM-18 Rotary Machine, 18" Throat Depth Sheet Metal Fabrication Bead Roller Plate steel body and sports a full 18 inch of throat depth, making it perfect for strengthening any type of panel such as roof, deck, and hoods This bead roller is manually operated by a hand crank that drives both the bottom and top bead rolls This bench mounted manually operated bead roller comes with the most popular sizes of forming rolls for HVAC work It comes with a roll rack and six sets of the most common rolls required by metal forming enthusiasts; 1/16", 1/8", 1/4" step dies and 1/4", 3/8", 1/2" bead dies