Q: Can zippers from different lots be used together?
Mixing zipper lots in one garment order is a common source of complaints, so the rule should be explicit. Two lots can be used together when they come from the same tape dye lot and the same teeth batch, and when the shade difference is inside the agreed tolerance under the agreed light source. They should not be mixed when the difference is visible on the garment, because a single jacket with a mismatched zip is a reject even if each piece passed on its own. A practical control is to keep the lot number on each carton and to instruct the cutting room to use one lot per style or per size range. If a lot must be split, check the two lots side by side first and record the decision. For a repeat programme, ask the supplier to reserve tape from one dye lot for the whole run. When in doubt, keep the lots separate and use the second lot on a style where the zip is less visible.