By far the most difficult header components to home fabricate, Hooker offers high quality stainless steel collectors. Formed on state-of-the-art collector forming machinery and offered in two sizes (1-3/4 in. primary tubing x 3 in. collector and 1-7/8 in. primary tubing x 3 in. collector), the two kits come in two styles. The Deluxe kit includes the collector and stainless steel band clamp but adds a high performance investment cast attenuation spear (creating similar flow dynamics to a merge collector design) along with an O2 bung for mounting your factory O2 sensor.