Review on SNUG Fasteners SNG586: High-Quality 1/4-20 Stainless Steel Nylon Insert Hex Lock Nuts - Pack of 50 by Juan Castillo

This nut will probably fit most people but I took off a star because the material is not exactly what is listed in the description. Most people probably don't care, but it irritates me a little when a manufacturer lists a certain type of material and replaces it with something else. These nuts are supposed to be 304 stainless steel, but they are actually 304Cu (see XRF analysis). This alloy consists essentially of 304 stainless steel with an added copper component. Copper was widely considered an impurity in recycled stainless steel due to it being missorted (and copper entering the alloy), however it is becoming more common in Asian (and some European) countries to include copper "on purpose" in SS304 because it is said to be the The resulting alloy is lighter and suitable for cold forming, for example thread forming. I put "on purpose" in quotes because I'm not sure if that's a legitimate reason or just being used as an excuse for inferior metals. In comparison, none of the stainless steel nuts and bolts I've tested from reputable manufacturers (both US and Asian) contain copper, so it's clearly not a production requirement. Allow this level of copper contamination in stainless steel, listed as "304". do you care Probably no. However, in addition to the supposedly easier cold workability of copper-containing SS304, SS304Cu has lower tensile strength than SS304 (albeit somewhat marginally) and appears to have improved corrosion resistance under sulphurous conditions (although stainless steel specified for resistance to sulfuric acid generally has this). a lower tensile strength than SS304). with a higher Cu content than this.). In addition to the material composition, I measured the small diameter thread gap (I don't have the proper tools to measure the large diameter gap), the diameter between flat surfaces, the point-to-point diameter, and the overall thickness. The diameters appear to be within spec and I was able to thread them onto a standard 1/4-20 bolt with no problem.