The most important QC checks for custom streetwear production include fabric quality, color consistency, shrinkage, measurement tolerance, stitching, seam strength, logo placement, embroidery quality, print durability, zipper function, snap buttons, drawcords, labels, hangtags, packaging, and final shipment inspection. For washed garments, QC should also include shade, hand feel, and post-wash measurements. For private label brands, QC should be confirmed before bulk production, not only after production is finished. A clear approved sample, measurement spec, and inspection checklist help reduce misunderstandings.