Simpson Strong-Tie S8SND1 Annular Ring Shank Siding Nail 13 ga. x 2.5 x 5/32 in.

High tensile nickel or chromium stainless steel will last the life of wood siding without degradation ever. Slender gauge and blunt diamond point minimize splitting. Generous under-head fillet allows nails to be driven flush or countersunk without crushing surrounding wood.

eBay