Hexagon Flange Head Cap Screw 3914407 covers many Cummins engines, including B3.3, B3.9, 6B5.9, 6C8.3, ISF2.8, F3.8, QSB, ISB, B4.5, B6.7, ISC, ISL8.9, M11, M15, NH, NT855, N14, ISX, K19, K50, and ISZ13. The flange head spreads load for a secure hold. OEM quality for strength and reliable fastening.