PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

BA1-3BGage,compound Pressure-Vacuum,di

Ellis & Watts International, Llc · NSN 6685-01-045-0491 · FSC 6685 · No Item Name Available
Verified by PartsTable
NSN 6685-01-045-0491 — this item is cataloged by the U.S. Government under National Stock Number 6685-01-045-0491. Primary manufacturer part number: BA1-3B.
Features
  • Gage,compound Pressure-Vacuum,di — FSC 6685
  • Overall Diameter: 2.750 INCHES NOMINAL IN
  • Pointer Type: INDICATING
  • Scale Inscription/background Color: BLACK MARKINGS ON WHITE BACKGROUND
  • Scale Range: +0.0 TO 30.0 INCHES OF MERCURY AND +0.0 TO 150.0 POUNDS PRESSURE PER SQUARE INCH LBS
  • Connection Quantity: 1
  • Scale Type: SINGLE
  • Material: STEEL CASE
Applications
  • Applications requiring Steel Case construction
General Description

The Gage,compound Pressure-Vacuum,di, cataloged under National Stock Number 6685-01-045-0491, is classified within Federal Supply Class 6685 (No Item Name Available) of the Instruments and Laboratory Equipment group. The primary manufacturer of record is Ellis & Watts International, Llc. Government technical data includes 25 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 4 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.

Technical Specifications
ParameterValue
NSN6685-01-045-0491
Primary Part NumberBA1-3B
Item NameGage,compound Pressure-Vacuum,di
FSC / FSG6685 / 66 — No Item Name Available
ManufacturerEllis & Watts International, Llc
StatusCANCELLED
Overall Diameter2.750 INCHES NOMINAL IN
Pointer TypeINDICATING
Scale Inscription/background ColorBLACK MARKINGS ON WHITE BACKGROUND
Scale Range+0.0 TO 30.0 INCHES OF MERCURY AND +0.0 TO 150.0 POUNDS PRESSURE PER SQUARE INCH LBS
Connection Quantity1
Scale TypeSINGLE
MaterialSTEEL CASE
Connection Size0.125 IN. NPT DIA IN
Connector Type VentNOT PROVIDED
Scale NamePRESSURE AND VACUUM
Connection LocationBOTTOM
Mounting MethodCASE
Connection TypeEXTERNAL
Graduation Unit15.0 INCHES OF MERCURY AND 25.0 POUNDS PER SQUARE INCH LBS
Scale Smallest Increment5.0 INCHES OF MERCURY (INHG) AND 5.0 POUNDS PER SQUARE INCH (PSI) LBS
Actuation TypeBOURDON TUBE
MaterialCOPPER ALLOY ACTUATING ELEMENT
Mounting Connection LocationBACK
Pointer ColorBLACK
MaterialPLASTIC ACRYLIC PROTECTIVE CRYSTAL
Scale AccuracyPORM 2 PCT MIDDLE HALF,PORM 3 PCT REMAINDER
Dial Size2-1/2 IN. DIA IN
Bezel TypeSLIPS-ON
AdjustabilityADJUSTABLE
Surface TreatmentENAMEL
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 4
6685-00-413-6670023266 INTERCHANGEABLE
Gage,compound Pressure-Vacuum,di
Bellofram Corporation
5120-00-473-74947078977 INTERCHANGEABLE
Inserter,seal
U S Army Tank Automotive Command Amsta-Im-Mm
4420-00-974-1733F9207-33-35-36 INTERCHANGEABLE
Heat E,changer Asse
Flair Corporation Dba S P X Air Treatment Div Dehydration
5365-01-381-402602325-1 INTERCHANGEABLE
Plug,machine Thread
Defense Logistics Agency Dba Defense Supply Center Philadelphia
Cross-Reference Index
Part NumberManufacturer
BA1-3B Ellis & Watts International, Llc (USA)
J4318 Desco Corp Marsh Bellofram Div (USA)
023-251 Bellofram Corporation (USA)
Related Parts
6685-00-413-6670INTERCHANGEABLE
GAGE,COMPOUND PRESSURE-VACUUM,DI
023266
5120-00-473-7494INTERCHANGEABLE
INSERTER,SEAL
7078977
4420-00-974-1733INTERCHANGEABLE
HEAT E,CHANGER ASSE
F9207-33-35-36
5365-01-381-4026INTERCHANGEABLE
PLUG,MACHINE THREAD
02325-1

Frequently Asked Questions

What is NSN 6685-01-045-0491?

NSN 6685-01-045-0491 is a Gage,compound Pressure-Vacuum,di, manufactured by Ellis & Watts International, Llc, classified under FSC 6685 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 6685-01-045-0491?

NSN 6685-01-045-0491 has 3 cross-referenced part numbers: BA1-3B (Ellis & Watts International, Llc), J4318 (Desco Corp Marsh Bellofram Div), 023-251 (Bellofram Corporation).

What NSN replaces 6685-01-045-0491?

There are 4 known substitutes for 6685-01-045-0491: 6685-00-413-6670, 5120-00-473-7494, 4420-00-974-1733 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of BA1-3B?

Key specifications for BA1-3B: Overall Diameter: 2.750 INCHES NOMINAL IN; Pointer Type: INDICATING; Scale Inscription/background Color: BLACK MARKINGS ON WHITE BACKGROUND; Scale Range: +0.0 TO 30.0 INCHES OF MERCURY AND +0.0 TO 150.0 POUNDS PRESSURE PER SQUARE INCH LBS. 26 total characteristics are documented in the Federal Logistics Information System.

Is NSN 6685-01-045-0491 still in active supply?

NSN 6685-01-045-0491 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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