What a CoA records, and how to match it to the material you hold.
A certificate of analysis (CoA) reports test results for one specific batch of material. It applies to that batch only, so the first check is always that the batch number on the certificate matches the batch number on the vial.
A typical CoA lists the product name, batch or lot number, each test performed, the method used, the acceptance limit (the specification), the result and the date of analysis. It usually identifies the laboratory that carried out the testing.
For peptides, purity is commonly measured by high-performance liquid chromatography (HPLC), which separates a sample into its components. Identity is commonly confirmed by mass spectrometry (MS), which measures molecular mass.
Where a CoA is available for a Syntha Labs product, it's listed in the Documentation section of that product's page.