Since it took me a day to figure out which Pelican cases to buy, I thought it would be useful to post. I wanted the largest, lightest option that would be allowed as checked luggage on American Airlines and British Airways without excess baggage fees.
The iM2875 Pelicans are “lightweight”, weighing 20 pounds with an additional 7 pounds of foam. The airlines limit the final weight to 51 pounds, so I can pack 30 pounds of gear and foam.