A standard pack of 20 pieces covers about 40 square inches.

Each piece is 1-1/8" x 4" x 0.012", fabricated from galvanized steel sheet. The ripples are about 0.1" peak to peak, which is 2-1/2" in 1:24 scale. Corrugated metal was manufactured in various sheet sizes, so this material will fit most outdoor scales.

Allow 1/8" overlap between pieces and rows, when calculating your roofing needs. Apply with any outdoor grade adhesive, or nail it down. (Caution: corners are sharp.)