Are these 316 SS? If not how do you find 316 replacment for beach application?

Hi Derry! Thanks for the question! The screws are 410 with a silver Ruspert coating. This railing is ideal for beach applications, as this railing is specifically covered under warranty for salt water applications. Here is a link to the warranty: https://assets.timbertech.com/content/dam/wp-content/TimberTech-rail-warranty-English-10.01.23.pdf. The exclusions are listed out on the first page; however, if you look just under the exclusions, you'll see a note that says: "Exclusion 10 (salt water exclusion) does not apply to Impression Rail and Impression Rail Express with infills other than cable rail with adherence to care and cleaning guidelines available at https://www.timbertech.com/resources/care-cleaning/#railing. For Impression Rail Express, Exclusion 10 applies to cable rail infills." I do hope this helps! Please feel free to give us a call at 877.275.2935 if you have any questions or need further assistance.