We prefer to receive sheet film in the manufacturer 3 piece boxes. Film boxes will be returned.
If you do not have access to the boxes, you could use a dark bag made for sheet film. They are available at bhphotovideo.com. Search for “Delta 1 Light Tight Safe-T-Bags”. If you use one of these bags, please pack carefully so it is not cut by postal equipment.
Please keep in mind that film holders are heavy, so please plan on selecting USPS Priority Mail or FedEx for return shipping if you send in the plastic film holders.
Make sure you identify exactly what kind of film is being submitted as many notch codes are very similar. Also, do not combine different film stocks in a bag or box.