Use t75 flask or similar. Seed cells. Fill with warm medium. Leave about 5 ml from the top. There will be a small air bubble in the flask when done. May want to use HEPES buffered medium due to the absence of CO2 in the system. Close lid firmly. Wrap lid with parafilm. Wrap flask with bubble wrap. Put in fed ex box. Fill dead space with bubble wrap, tissue, or popcorn. Send package overnight.