Metric T nuts for bed rail

Nuts, Bolts & Washers stainless steel t slot bolts to work with most standard t-slot rails and is optimized for 14 gap sizes It is machined from a solid piece of stainless steel right here in the USA stainless steel slot drain M8 x 25mm T-Slot Drop-in Stud Sliding Bolts T Shape Screws, 304 Stainless Steel 18-8, Plain Finish, Fully Threaded, 10 PCS uxcell M8x45mm T Slot Drop-in Bolt,

stainless slot drain I see one company uses stainless steel anchors with aluminum profiles Others use zinc Is this an issue or is that only for untreatednon-