PPS (Pre-Production Sample)
A sample made with the actual materials and process before mass production, approved by the buyer as the reference for the full order.
TL;DR: A PPS is a sample made just before mass production, using the same materials, methods, and settings planned for the full order. Once the buyer approves it, it becomes the standard the finished goods are checked against.
A PPS is different from an early prototype or a catalog sample. Its purpose is to confirm that the factory can produce exactly what was agreed, at production quality. Typical checks include color, size, finish, workmanship, labeling, and packaging.
For custom glass mosaic murals, a PPS is often a color swatch board or a sample section of the mural. The buyer compares the tile colors and the rendering of the image against the approved design, ideally under lighting similar to the final site. Glass colors can look different on screen, under daylight, or underwater in a pool, so a physical sample reduces the risk of surprises.
Approve the PPS in writing, and keep one signed or marked sample on each side if possible. This gives the buyer, the supplier, and any inspector the same reference. A PSI (Pre-Shipment Inspection) or Third-Party Inspection can then compare the finished goods with the approved sample.
Sending a PPS to an overseas buyer adds time, usually by Express Courier Shipping. If time is short, some buyers approve from detailed photos and videos, but this is less reliable for color. Build sample approval into your Lead Time plan from the start.