The L.H. Dottie 381HCS is a 3/8" x 16 x 1" C/S Zinc Hex Bolt. Hex Head Tap Bolts can be fastened into internally tapped holes or used with a nut to pull assemblies together over a long length. For adjustment applications, they may be used with jam nuts to secure the assembly in place. They are manufactured to the IFI-199 standard.