Bacta Canister
Bacta Canisters replenish health, just like Med Packs, the only difference is, that Bacta Canisters aren't instant.
Bacta Canisters give 50 health, Big Bacta Canisters give 100 health.
You will have to select the Bacta Canister, and use it, to replenish your health.
Only 1 Bacta Canister can be carried at any given time.