A zipper guide for use in a slider insertion machine in which the zipper guide can be easily loaded with zipper tape without disassembly of the zipper guide. The slider insertion apparatus comprises: an assembly for inserting sliders onto a zipper tape; first and second shafts that are fixed relative to the assembly; a zipper guide for guiding the zipper tape during longitudinal movement of the zipper tape and supporting the zipper tape during slider insertion; and a retainer coupled to the first shaft and movable between first and second retainer positions. The zipper guide comprises a stationary part that is fixed relative to the assembly and comprises a first groove, and a rotatable part that is rotatable about the second shaft between first and second angular positions and comprises a second groove. The retainer is coupled to the rotatable part in the first retainer position to block rotation of the rotatable part and is uncoupled from the rotating part in the second retainer position to not block rotation of the rotatable part.