Make-A-Zipper is a 197" roll of 2.5 nylon (2.5 mm wide teeth) with 12 attached matching slides. It is even narrower than so-called "doll zippers", which use a3 mm wide tooth.

Because the zipper chain is nylon, the slides are bi-directional: whatever the first slide does, the second will do the opposite if placed on the same section of zipper. One slide is all you need, but go ahead, get wild, use two!