Now even cast iron exhaust manifolds can benefit from Thermo-Tec's insulation technology! This blanket wraps around the exhaust manifold or header, clipping in place to retain exhaust heat and keep underhood temperatures low. Loose design is less restrictive (and thus less damaging) than header wrap, and is much easier to install than wrapping individual header tubes. Aluminized outer coating even makes spilled fluids easier to clean up than untreated header wrap. Fits most inline 4 or 6 cylinder engines (use two for V6, V8, V10, or V12 engines).