A reference sample is a garment that is similar in size and shape to the garment that you want to create. It is not used to replicate the garment you are designing, but to guide your fashion designer on spec measurements, shape and fabric feel.
The reference sample needs to be the same size (but not entirely the same shape) as the sample size for your tech pack. Grading of sizes is only created after you have approved your final Proto or SMS sample. Read more about sample types, cost and lead times. You would want to pick the size that you will use for your fit model.
If you don’t have a reference sample, it means that you might run into more sample rounds than if you had one. Without reference samples, the fashion designer will need to guess more on measurements and the tech packs might not reflect the correct specs and shapes as accurately, resulting in a more time-consuming process and wastage of materials. Finding a reference sample is part of the research and development phase of the design process.
Design Handover + Reference Sample = Tech Pack!