The O-Ring, cataloged under National Stock Number 5331-00-125-7661, is classified within Federal Supply Class 5331 (O-ring) of the Hardware and Abrasives group. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
Catalog Facts
Item Name
O-Ring
FSC / FSG
5331 — O-ring (FSG 53)
Technical Specifications
Parameter
Value
NSN
5331-00-125-7661
Item Name
O-Ring
FSC / FSG
5331 / 53 — O-ring
Status
ACTIVE
Lifecycle & Compliance
Acquisition Status
ACTIVE
DEMIL Code
DEMIL A — No Demilitarization Required
Hazard
No hazard code in the DLA record (HMIC N)
⇄Related Items3
Each row states its source: a government interchangeability/replacement code, or a possible match on a shared part number.
5365-00-203-438399924POSSIBLE MATCH
PLUG,MACHINE THREAD
Possible match (shared part number)Pratt & Whitney Canada Corp Div Pratt & Whitney Canada Corp.
5331-01-055-8750POSSIBLE MATCH
O-RING
Possible match (shared part number)
2540-01-372-401899924POSSIBLE MATCH
INSULATION,VEHICULAR
Possible match (shared part number)Stewart & Stevenson Power Products Llc
Cross-Reference Index
No manufacturer part numbers on file in the U.S. Government catalog.
Reference documents
Reference
Meaning
405331
3/9Design control — primary reference
Kline Manufacturing Co Inc
99924
5/9Secondary reference
Kline Manufacturing Co Inc
Related Parts
5365-00-203-4383POSSIBLE MATCH
PLUG,MACHINE THREAD
99924
5331-01-055-8750POSSIBLE MATCH
O-RING
2540-01-372-4018POSSIBLE MATCH
INSULATION,VEHICULAR
99924
Frequently Asked Questions
What is NSN 5331-00-125-7661?
NSN 5331-00-125-7661 is a O-Ring, classified under FSC 5331, O-ring. Status: active.
What NSN replaces 5331-00-125-7661?
3 possible matches (shared part number, not a government interchangeability claim): 5365-00-203-4383, 5331-01-055-8750, 2540-01-372-4018. Verify interchangeability with system specifications before substitution.
Is NSN 5331-00-125-7661 hazardous material?
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
Sources
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.
✓ Data cited from the U.S. Government catalog; commercial cross-references from OEM and certified industry sources.