A zipper strip for a reclosable package having a transverse zipper is provided. The zipper strip comprises a male interlocking profile and a female interlocking profile. Each profile includes an interlocking member and an integral web which defines a leading flange. The leading flanges are sealed to thermoplastic film material which is used to make the reclosable packages and to each other. A perforation extends along the length of the zipper strip so that the profiles can be readily separated.