The U.S. aircraft register, updated daily
Parts

External Liquid

No failure report names the external liquid. 1 FAA approvals let 1 company make a replacement external liquid, Air Methods CORP International holding the most (1).

Approved replacement parts 1 parts manufacturer approvals

A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a external liquid and sell it as an approved part for the models named. These are the companies holding such approvals for a external liquid:

For these models most: Airbus Helicopters EC-135 now H135 (1).

MakerPartReplacesFitsGrantedStatus
Air Methods CORP InternationalExternal Liquid Oxygen (LOX) System MDL 731-9036Modification PartsEurocopter Deutschland EC 135 P1 P2 P2+ T1 T2 T2+2009-03-10current

Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.