SNUG Fasteners (SNG593) 20 Qty 5/16-18 Stainless Steel Acorn Hex Cap Nuts

For my purpose i.e. caps for new metal stair railing posts these cap nuts are perfect. They are nicely polished, strong and good quality resulting in a professional look.

Good nut, good easy threading, great outer shell, worked great

As described

Everything I expected

Bought these for some decorative bollards. Worked great. Better quality than I expected.

Product arrived on time and was exactly as stated in description.

stainless acorn nuts, what's not to like?

I ordered two sizes of these SS nuts. I was pleased to see that both sizes were threaded all the way to the top of the cap and had no burrs. I threaded them all on bolts and they threaded smoothly.Since the 1/2" turned out to be too large for my use, I tested rust resistance with some of them. I looked up how materials engineers test stainless coatings and one method is to place the items in a humidity chamber for 2 hours at 100 deg. I took it a step further...I placed one nut each in 2 plastic jars and sealed them for 8 days in my shed where temperatures reach over 100 deg. One nut was submerged in well water and the other was suspended above well water so it was subjected to high humidity. After 8 days the submerged nut showed slight rust in its threads. The non-submerged nut was covered in condensation but had no visible rust. I was pleased! The rust in the threads was to be expected since I damaged the coating by threading it on a bolt. SS coatings are self-healing but I started the test immediately after threading it so the coating did not have a chance.The outside of the nut, where the finish was undamaged, had no rust, which is closer to real world applications.