PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

MIL-DTL-18866Reducer,tube

Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M · NSN 4730-00-727-7387 · FSC 4730 · No Item Name Available
Verified by PartsTable
NSN 4730-00-727-7387 — this item is cataloged by the U.S. Government under National Stock Number 4730-00-727-7387. Primary manufacturer part number: MIL-DTL-18866.
Features
  • Reducer,tube — FSC 4730
  • Nominal Outside Diameter Tube Accommodated: 0.375 INCHES SECOND END IN
  • Connection Style: SWIVEL NUT, FLARE (TUBE) STYLE 3 OPTIONAL END FIRST END
  • Seat Angle: 37.0 DEGREES ALL ENDS
  • Connection Type: THREADED INTERNAL TUBE FIRST END
  • Material: STEEL CORROSION RESISTING OVERALL
  • Connection Style: FLARELESS (TUBE) SECOND END
  • Nominal Thread Size: 0.562 INCHES SECOND END IN
Applications
  • Fluid conveyance
  • Hydraulic system plumbing
  • Pneumatic line routing
  • Applications requiring Steel Corrosion Resisting Overall construction
General Description

The Reducer,tube, cataloged under National Stock Number 4730-00-727-7387, is classified within Federal Supply Class 4730 (No Item Name Available) of the Pipe, Tubing, Hose, and Fittings group. The primary manufacturer of record is Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M. Government technical data includes 18 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 21 commercial cross-references from 13 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
NSN4730-00-727-7387
Primary Part NumberMIL-DTL-18866
Item NameReducer,tube
FSC / FSG4730 / 47 — No Item Name Available
ManufacturerMilitary Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
StatusCANCELLED
Nominal Outside Diameter Tube Accommodated0.375 INCHES SECOND END IN
Connection StyleSWIVEL NUT, FLARE (TUBE) STYLE 3 OPTIONAL END FIRST END
Seat Angle37.0 DEGREES ALL ENDS
Connection TypeTHREADED INTERNAL TUBE FIRST END
MaterialSTEEL CORROSION RESISTING OVERALL
Connection StyleFLARELESS (TUBE) SECOND END
Nominal Thread Size0.562 INCHES SECOND END IN
Reducer TypeCONCENTRIC
Nominal Overall Length1.000 INCHES IN
Surface TreatmentPASSIVATE OVERALL
Nominal Outside Diameter Tube Accommodated0.500 INCHES FIRST END IN
Thread Class2A ALL ENDS A
Surface Treatment Document and ClassificationQQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
Nominal Thread Size0.750 INCHES FIRST END IN
Specification/standard Data96906-MS51534 GOVERNMENT STANDARD
Furnished Items and Quantity1 TUBE COUPLING NUT W/SLEEVE
Thread Series DesignatorUNF ALL ENDS
Connection TypeTHREADED EXTERNAL TUBE SECOND END
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 4
4730-00-786-2247 INTERCHANGEABLE
Reducer,tube
4730-00-835-3767 INTERCHANGEABLE
Reducer,tube
6740-01-428-035106010729 INTERCHANGEABLE
Processing Machine,photographic
Fujifilm North America Corporation
4920-01-571-8338 INTERCHANGEABLE
Reducer,tube End,ai
Cross-Reference Index
Part NumberManufacturer
MIL-DTL-18866 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
8-6TRBTXSS Parker Hannifin (uk) Ltd (GBR)
06060300 Terex Aerials Inc (USA)
8-6TRBTXSS Parker Hannifin Corp Dba Pneutronics Div Stratoflex Products Division (USA)
729-100 Malabar (USA)
8-6TRBTXSS Parker Hannifin (uk) Ltd (GBR)
12265133 Globe Fasteners Inc (USA)
MS51534-B8S6 Military Standards Promulgated by Military Departments Under Authority of Defense Standardization Manual 4120 3-M
1049529-3 Allied-Signal Inc Dba Allied-Signal Aerospace Co Electrodynamics Div (USA)
MS51534A8-6S Military Standards Promulgated by Military Departments Under Authority of Defense Standardization Manual 4120 3-M
8-6TRTXS Parker-Hannifin Corporation Dba Pneutronics Div Corporate Headquarters (USA)
35027X8X6 Dana Corp Weatherhead Div (USA)
SK56546-462 Atk Launch Systems Llc Dba Atk Launch Systems-Promontory Div Propulsion Systems - Promontory (USA)
MS51534A8-6S Parker Hannifin Corp Dba Pneutronics Div Stratoflex Products Division (USA)
8-6TRBTXSS Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division (USA)
MS51534A8-6S Parker-Hannifin Corporation Dba Pneutronics Div Tube Fittings Division (USA)
8-6TRBTX-SS Parker-Hannifin Corporation Dba Pneutronics Div Corporate Headquarters (USA)
AA67034-8-6 Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply (USA)
8-6TRX-SS Parker-Hannifin Corporation Dba Pneutronics Div Corporate Headquarters (USA)
MS51534B8-6S Military Standards Promulgated by Military Departments Under Authority of Defense Standardization Manual 4120 3-M
Related Parts
4730-00-786-2247INTERCHANGEABLE
REDUCER,TUBE
4730-00-835-3767INTERCHANGEABLE
REDUCER,TUBE
6740-01-428-0351INTERCHANGEABLE
PROCESSING MACHINE,PHOTOGRAPHIC
06010729
4920-01-571-8338INTERCHANGEABLE
REDUCER,TUBE END,AI

Frequently Asked Questions

What is NSN 4730-00-727-7387?

NSN 4730-00-727-7387 is a Reducer,tube, manufactured by Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M, classified under FSC 4730 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 4730-00-727-7387?

NSN 4730-00-727-7387 has 21 cross-referenced part numbers: MIL-DTL-18866 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), 8-6TRBTXSS (Parker Hannifin (uk) Ltd), 06060300 (Terex Aerials Inc), 8-6TRBTXSS (Parker Hannifin Corp Dba Pneutronics Div Stratoflex Products Division), 729-100 (Malabar) and 16 more.

What NSN replaces 4730-00-727-7387?

There are 4 known substitutes for 4730-00-727-7387: 4730-00-786-2247, 4730-00-835-3767, 6740-01-428-0351 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of MIL-DTL-18866?

Key specifications for MIL-DTL-18866: Nominal Outside Diameter Tube Accommodated: 0.375 INCHES SECOND END IN; Connection Style: SWIVEL NUT, FLARE (TUBE) STYLE 3 OPTIONAL END FIRST END; Seat Angle: 37.0 DEGREES ALL ENDS; Connection Type: THREADED INTERNAL TUBE FIRST END. 18 total characteristics are documented in the Federal Logistics Information System.

Is NSN 4730-00-727-7387 still in active supply?

NSN 4730-00-727-7387 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.
PartsTable Design LLC · partstable.com