Size & weight
Measured length, width and piece weight, with allowed tolerances stated.
Before bulk production, we check size, fabric, color, workmanship and packaging on physical samples. What both sides approve is written into a specification, and production and inspection follow it from then on.

Using linen as an example, these are the points usually checked one by one when approving samples. Other categories are adjusted to suit the product.
Measured length, width and piece weight, with allowed tolerances stated.
Check composition and weave, comparing again after washing if needed.
Check against color codes in natural light, and check logo position, size and method.
Stitching, binding and stitch density, plus unit packaging and label content.

Not every project needs all three rounds. Standard products may be approved in one go; custom products usually need several rounds of adjustment.
Most differences between bulk goods and samples come from something not written down at the start. When approving samples, write the standard into the specification.
Tell us which products and specifications to sample, and where to send the samples. If you have a reference sample, you can also send it to us for comparison.
Upload RFQPrice, lead time and shipping method are confirmed against your specific list.