Each PPE Performance Silicone Hose is strengthened with 5 plies of Nomex reinforced fibers making them very tough. Fluorocarbon lining offers better lubricity (slippery and resistant to chemicals) and the silicone rubber construction ensures they can withstand constant boost pressures and temperatures from -76 degrees all the way to +437 degrees Fahrenheit. PPE silicone will maintain structural integrity even when subject to high boost pressures throughout the temperature range. In short, PPE Pe