Proflow Turbo Heat Shield, Titanium Turbo Blanket, T3/T4, GT30-35/GT40 - PFEHS-BST-TITB-T3T4Part Number: PFEHS BST TITB T3T4 Proflow's titanium turbo beanies use a volcanic rock fibre outer layer with a high temperature rated silica insulation matting as the inner layer. This adds an extra layer of protection against extreme turbo generated heat. These will prevent heat from damaging the surrounding engine components such as wiring, hoses and plastics. They also help to regulate exhaust gas temperature to maintain turbo efficiency.