I was wondering how people ship ink samples to others. I'm hoping to get started with the ink sample exchange soon. However, I am unsure how people ship 5 mL plastic tubes filled with ink to each other. Specifically, I have the following two questions: 1. How do you all recommend packaging small, plastic vials of ink so that they will reach their destination intact and without earning the ire of the shipper. Is putting the vials in a plastic bag inside a basic envelope sufficient? Or is more packaging necessary? If so, how should I package them instead? 2. A U.S. specific question. Is it okay to mail the ink samples out by depositing them in an outdoors USPS collection box? If so, how many stamps should I use? Thank you for any help.