Which carrier should I use for shipment?

Whichever is most convenient for you; we recommend UPS or FedEx for faster shipping. It is best to send the samples priority overnight so we get them by 10:30 a.m. If you send them standard overnight, we may get them in the morning but sometimes we do not get standard overnight shipments until after 3 p.m. which can delay the results. If you choose to send samples USPS, please understand that there may be an extra day for turnaround as we do not receive those packages until late in the afternoon.