Zipper Types

Open-end zipper
Zipper that can be separated from one side.

Closed-end zipper
Zipper that can't be separated from any side.

Open-end zipper with two sliders
Zipper with two sliders, both of which can be separated.

Closed-end zipper with two sliders - O-variant
Zipper with two sliders, none of which can be separated.

Closed-end zipper with two sliders - X-variant
Zipper with two sliders, none of which can be separated.