NS-3913-G1 is an extreme pressure fortified grease designed for couplings and gears. High film strength components provide long lasting protection. EP and anti-wear additives along with rust inhibitors provide excellent performance for applications ranging from aerospace such as helicopter drive shaft couplings and bearings to industrial applications such as steel mill gear couplings. NS-3913-G1 is the only lubricant approved by Bell Helicopter Textron for use on their Crown Gear Driveshaft couplings.