INDIEFLOW refills are single-use. They must be changed after each deployment. In the event of a side fall, only the airbag corresponding to the side of the fall will deploy. It is therefore not necessary to change the INDIEFLOW refill on the side of the airbag that has not deployed. There are 2 sizes of INDIEFLOW refill depending on the size of the airbags (size 1 for S and M airbags, size 2 for L and XL airbags).