The Propellant Pressurizing Agent,he, cataloged under National Stock Number 9135-01-644-2554, is classified within Federal Supply Class 9135 (Liquid Propellant Fuels and Oxidizers, Chemical Base) of the Fuels, Lubricants, Oils, and Waxes group. Government technical data includes 4 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 4 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 9135-01-644-2554 |
| Item Name | Propellant Pressurizing Agent,he |
| FSC / FSG | 9135 / 91 — Liquid Propellant Fuels and Oxidizers, Chemical Base |
| Status | ACTIVE |
| Unpackaged Unit Weight | 213.0 CUBIC FEET NOMINAL |
| Unit Package Type | CYLINDER |
| Composition and Percentage | 99.995 MINIMUM BY VOLUME HELIUM |
| Supplied Cylinder | SUPPLY ITEM |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Hazardous per DLA record (HMIC D) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| M27407-1A CYL | 2/2 Government specification standardization U.S. Government activity |
| MIL-PRF-27407 | 4/1 Identification reference U.S. Government activity |
NSN 9135-01-644-2554 is a Propellant Pressurizing Agent,he, classified under FSC 9135, Liquid Propellant Fuels and Oxidizers, Chemical Base. Status: active.
4 possible matches (shared part number, not a government interchangeability claim): 9135-01-665-9405, 9135-01-665-9490, 9135-01-665-9887. Verify interchangeability with system specifications before substitution.
Key specifications for 9135-01-644-2554: Unpackaged Unit Weight: 213.0 CUBIC FEET NOMINAL; Unit Package Type: CYLINDER; Composition and Percentage: 99.995 MINIMUM BY VOLUME HELIUM; Supplied Cylinder: SUPPLY ITEM. 4 specifications are documented in the U.S. Government catalog.
Hazardous per DLA record (HMIC D). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.