The Reducer,air Conditioning-Heating, cataloged under National Stock Number 4520-01-391-3248, is classified within Federal Supply Class 4520 (Space and Water Heating Equipment) of the Plumbing, Heating, and Waste Disposal group. Government technical data includes 5 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
Technical Specifications
Parameter
Value
NSN
4520-01-391-3248
Item Name
Reducer,air Conditioning-Heating
FSC / FSG
4520 / 45 — Space and Water Heating Equipment
Status
ACTIVE
Style Designator
REDUCING
Sheet Metal Gage Size
22
Surface Treatment
ZINC
Material
STEEL
Diameter
20.000 INCHES IN
Lifecycle & Compliance
Acquisition Status
ACTIVE
DEMIL Code
DEMIL A — No Demilitarization Required
Hazard
No hazard code in the DLA record (HMIC N)
Criticality Code
X
Cross-Reference Index
No manufacturer part numbers on file in the U.S. Government catalog.
Reference documents
Reference
Meaning
SRHQR-12 20"/20" TO 20"0
3/9Design control — primary reference
United Mcgill Corp
No interchangeability data on file.
Other items in FSC 4520 — Space and Water Heating Equipment
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
4520-00-000-0098
HEATING ELEMENT,ELECTRICAL,NONIM
4520-00-000-0099
4520-00-000-0099 · Item name not on file
4520-00-001-1240
4520-00-001-1240 · Item name not on file
4520-00-001-3518
HEATING ELEMENT,ELECTRICAL,NONIM
4520-00-001-3519
HEATING ELEMENT,ELECTRICAL,IMMER
4520-00-001-6052
HEATING ELEMENT,ELECTRICAL,NONIM
4520-00-001-6298
HEATING ELEMENT,ELECTRICAL,NONIM
4520-00-001-7726
HEATER,DUCT TYPE,PORTABLE
Frequently Asked Questions
What is NSN 4520-01-391-3248?
NSN 4520-01-391-3248 is a Reducer,air Conditioning-Heating, classified under FSC 4520, Space and Water Heating Equipment. Status: active.
What are the specifications of 4520-01-391-3248?
Key specifications for 4520-01-391-3248: Style Designator: REDUCING; Sheet Metal Gage Size: 22; Surface Treatment: ZINC; Material: STEEL. 5 specifications are documented in the U.S. Government catalog.
Is NSN 4520-01-391-3248 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.