Unique Design with Base Mounted Canister The OES HYDRA carbon dioxide absorber has a unique absorbent canister which is attached to the underside by two toggle clamps for easy removal and replacement, any liquid from breathing circuit condensation is retained in the bottom of the canister preventing contamination and allowing easy disposal. The absorber has a bypass valve, which allows the canister to be removed in the off mode without loss of fresh gas flow during absorbent replacement.