I got a similar product from my dentist as a free sample, though it's not the Chapstick brand. The dispenser is 1.5 in. long and weighs 3 gm; a regular Chapstick is 3 in. long and weighs 4 gm...not a huge weight savings, but it fits more easily in my pocket.
Thanks for the tip on refilling it, I never thought of that before!