Do it 8d x 2-1/2 In. 9 ga Hardened Steel Fluted Masonry Nails (29 Ct.)

Thick, flat head, made of hardened steel and fluted shank to aid in driving and holding power. For attaching furring strips and floor plates to concrete. The 6 oz. box is PVC, hang-up package. 9-gauge, 0.148 diameter shank and 11/32" diameter head.