There are three types of stainless steel commonly used for fasteners: 18-8, 304 and 316. The easiest way to look at it is to remember: the higher the type number the higher the corrosion resistance. Meaning, 18-8 stainless steel is less corrosion resistant than 304 and 316 stainless steel offers more corrosion resistance than 304.
While boaters often focus on the corrosion resistance properties, there is a cost to this extra protection:
strength. Because of the alloy composition, there are differences in the tensile strengths of each type of
stainless steel. To simplify it: the more corrosion resistant the fastener, the lower tensile strength. In
many cases this difference is minor and opting for the more corrosion resistant material will not affect the
holding power. In other cases, the choice of a weaker material can make a difference.
For highly loaded hardware that is under a load which is in-line with the fasteners (a tensioned load) 304 stainless steel may be a better choice.
Strut & Support Solutions offer both Grade 304 and Grade 316 Fastener Kits to suit your application. Check them out here.