These files are for printed replacement chains for the z-axis on V0 printers. The original "stock" parts were created by Tinpec and included here for convenience.
The modified "anchor" pieces replace both the original "top" and "adapter pieces. You only need one anchor piece; there are two slightly different versions, with one having more clearance for bulky wires and the other being a little more polished.
The "link_slotted" piece is intended to replace some of the original links towards the lower end of the chain where it will not move. They slot into the 1515 extrusions.
In summary, for a stock build size you will need one "stock_bottom", 18 "links" (with up to 8 being the "slotted" variant), and one top anchor (this can be "anchor_closed", "anchor_open", or both of "top" and "adapter" To assemble this chain you will also need a small length of 6mm 2GT belt and some 1.75mm filament to capture the belt in the end links. The belt you use for this can be of any quality.