icengineworks Series 1750EH Collector Dummies for 1-3/4" OD Header Assembly are designed for replicating formed or rolled exhaust collectors. By clamping, spot welding or bolting down the CD in the space reserved for the exhaust collector, builders can confidently design the exhaust header runners with precisely defined end points. During fabrication, the CDs will guide the proper alignment and trimming of the metal sections prior to actual welding. They create exhaust header runner assemblies that feature parallel end tubes for a quick exhaust collector weld. CDs are reusable and feature 100% Stainless Steel construction. Available in 3-into-1, 4-into-1, and 5-into-1 configurations and sold individually or as sets of 2.