Reduces Under-Hood Temperatures up to 70% Increases Horsepower & Fuel Efficiency Withstands Heat up to 2000 Degrees (2) 20 X 24 Blankets For V6 & V8 Applications The Header Manifold Blanket provides excellent heat-retention for exhaust headers and manifolds. This flexible heat shield simply clips into place on the upper portion of the header. The fabric side of the material should be facing the heat source, and the aluminized side facing away - offering protection from abrasion and harmful liquid spills.