Re: 304 stainless steel
The strenght characteristic of either 304, 316 or 321 SST for a cleat application is fine. The main differences in these materials is their corrosion resistance. 304 will work just fine, but 316 does have better corrosion resistance in a salt water environment. (316 is also a food grade and surgical grade SST.) When welding is performed, 321 SST is the material to go with.
The really big differences in corrosion resistnace occur when you start comparing SST hardware to chrome plate zinc hardware. If you're in a saltwater environment, the SST will outlast the chrome plated zinc. Personally, I go for 316 or 321 everytime if I have the option because my rig is always in saltwater.
