Used for applying slate and tile roofing. No unsightly rust, will not bleed or stain siding. Etched finish for great holding power. Recommended nail coverage for aluminum or vinyl siding is 100 nails per square. 1 lb. boxes. Aluminum nails cannot rust. They eliminate premature painting from rust streaks and stains caused by ordinary nails. Aluminum nails last indefinitely. Packed 50 boxes per carton.