Amazon offers its Prime members the Mr. Heater 1-lb. Propane Tank Refill Adapter
, model no. F276172, for $12.39
with free shipping
. (Non-members can get free shipping with orders of $25 or more; otherwise, shipping adds $5.25.) That's the lowest total price we could find by $5. It can be used to refill 1-lb. propane tanks.