BRAD PENN Compressed Natural Gas Engine Oil is a premium multi-viscosity lubricant specifically designed for use in compressed natural gas (CNG) fueled vehicles. It is recommended for use in Detroit Diesel 50G and 60G Series natural gas fueled engines and for use in Mack CNG (utilizing Cummins CNG engines) and in Cummins B, C and L-10 Series stationary and vehicular engines fueled by CNG. The oil is approved by Cummins against its CES 20074 specification and approved against Detroit Diesel DDC 93K216.