The stainless acorn cap nuts are 100% stainless steel 18-8 which offers a high level of chemical and corrosion resistance.
Stainless six sided cap nuts are great for general applications and wet environments. They are strong, corrosion proof, and will support all of your project purposes.
Material: Stainless Steel 18-8; Finish: Black Finish.
Inside Diameter: 0.138 Inch (#6); Thread Pitch Size: 32 TPI.