Typically manufactured from either low carbon steel or stainless steel, cap nuts, also referred to as acorn nuts are used to cover exposed bolt ends and add a finished appearance. These stainless steel cap nuts are composed of a hex nut and top cap consisting of 18% chromium and 8% nickel for corrosion resistance. Good for exterior and most marine applications.

Finished Hex Nuts in 18-8 stainless steel are designed for use with stainless steel bolts or screws with a specified minimum tensile strength equal or less than the specified proof stress of the mating nut. 18-8 nuts are made from one of the following austenitic alloys: 303, 303SE, 304, XM7, all of which are characterized as having a chromium content of 18% and nickel content of 8-10%. Hardness of Rockwell B95 - C32 for diameters 1/4 through 5/8. Rockwell B80 - C32 for diameters of 3/4 through 1 inch. Proof load of 100,000 psi for diameters 1/4 through 5/8 and 85,000 psi for diameters 3/4 through 1 inch.

Finished Hex Nuts in 316 stainless steel are designed for use with stainless steel bolts or screws with a specified minimum tensile strength equal or less than the specified proof stress of the mating nut. 316 stainless steel differs from 18-8 by it's molybdenum content (2-3%) and a higher nickel content (10-14%). This gives 316 stainless steel a higher degree of corrosion resistance and superior strength at raised temperatures. Hardness of Rockwell B95 - C32 for diameters 1/4 through 5/8. Rockwell B80 - C32 for diameters of 3/4 through 1 inch. Proof load of 100,000 psi for diameters 1/4 through 5/8 and 85,000 psi for diameters 3/4 through 1 inch.

Hex nut with a nylon-filled collar at its back end. When a screw reaches the collar, the threads and nylon form a tight, frictional fit, restricting movement of the screw when it is subjected to vibration. Designed to be used with like-material machine screws and bolts. It is able to be reused more times than a two-way reversible nut, however, nylon will begin to deteriorate at temperatures from 150℉ - 350℉. 18-8 stainless steel is best for applications where corrosion resistance is required.

These hex nuts in 18-8 stainless steel are for use with stainless steel machine screws in the corresponding diameter.