The O-Ring, cataloged under National Stock Number 5331-00-853-6655, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. The manufacturer of record is Sae International Dba Sae International. Government technical data includes 6 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 9 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5331-00-853-6655 |
| Primary Part Number | MS29561-243 |
| Item Name | O-Ring |
| FSC / FSG | 5331 / 53 — O-ring |
| Manufacturer | Sae International Dba Sae International |
| Status | ACTIVE |
| Cross-Sectional Height | 0.135 INCHES MINIMUM AND 0.143 INCHES MAXIMUM IN |
| Outside Diameter | 4.387 INCHES NOMINAL IN |
| Hardness Rating | 70.0 SHORE DUROMETER A NOMINAL |
| Elongation Percentage | 250 MAXIMUM |
| Center Hole Diameter | 4.094 INCHES MINIMUM AND 4.124 INCHES MAXIMUM IN |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| MS29561-243 | Leonardo Spa Helicopters Division - Production Site (ITA) |
| MS29561-243 | Aertekno S.r.l. (ITA) |
| MS29561-243 PRIMARY | Sae International Dba Sae International (USA) |
| Reference | Meaning |
|---|---|
| 1866-21 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
| 5331PL1185301 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
| 2-243 N4771-70 | 5/9 Secondary reference Parker Hannifin Gmbh O-Ring Division |
| 497250-315 | C/1 Advisory reference — outside the item-of-supply concept L3harris Maritime Power & Energy Solutions, Inc. Dba Spd Electrical Systems, Inc. |
| MS29561-243 | 5/9 Secondary reference U.S. Government activity |
| MS29561-243 | 3/9 Design control — primary reference U.S. Government activity |
| 2-243 47-071 | 5/9 Secondary reference Parker-Hannifin Corp Div O-Ring Division |
| SAE-AS29561 | 3/1 Design control — primary reference Sae International Dba Sae International |
| 2-243C0MP0UNDNU | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
NSN 5331-00-853-6655 is a O-Ring, manufactured by Sae International Dba Sae International, classified under FSC 5331, O-ring. Status: active.
NSN 5331-00-853-6655 has 3 manufacturer part numbers on file: MS29561-243 (Leonardo Spa Helicopters Division - Production Site), MS29561-243 (Aertekno S.r.l.), MS29561-243 (Sae International Dba Sae International).
1 possible match (shared part number, not a government interchangeability claim): 5930-01-668-1992. Verify interchangeability with system specifications before substitution.
Key specifications for MS29561-243: Cross-Sectional Height: 0.135 INCHES MINIMUM AND 0.143 INCHES MAXIMUM IN; Outside Diameter: 4.387 INCHES NOMINAL IN; Hardness Rating: 70.0 SHORE DUROMETER A NOMINAL; Elongation Percentage: 250 MAXIMUM. 6 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). 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.