The Canister is the housing for the concentrator, the collectors, and the mechanisms for deploying the collectors. It is mounted within the SRC and is returned to Earth in its entirety.
The canister design is robust, sufficient to withstand launch and re-entry G loads. The overall payload design achieves an ultra-clean environment within the canister by excluding practically all sources of outgassing. While the solar wind collectors reside within the canister, most mechanisms and electronics mount outside of the Canister.