Performance Exhaust Header 86-96 Suzuki Samurai Sidekick Geo Tracker 1.3L & 1.6L 1986-1996 Suzuki Samurai 1.3L and 1989-1994 Suzuki Sidekick 1.6L 8-Valve Engine and 1989-1994 Geo Tracker 1.6L 8-Valve Engine Tube Diameter: 1-3/8". Collector Diameter: 2-1/2". Mandrel-Bent Mild Steel Tubing. Thick Steel Flanges Gaskets included (Reuse OEM Header Bolts). Quality & Affordable Products Instruction not included. Professional installation recommended