Eaton 155S9-12D - Aeroquip Dust Plug Assembly Size 12

The Eaton Aeroquip 155S9-12D is a size 12 dust plug assembly engineered to protect the male half of Aeroquip 145/155 Series self-sealing quick-disconnect couplings when not in service. Compatible with -10 and -12 tube size coupling halves, this plug is a critical maintenance consumable for MRO facilities, military flightline operations, FBOs, and ground support equipment (GSE) shops that rely on the 145/155 Series — the standard ground service quick-disconnect for virtually all U.S. military aircraft for over 60 years — for aircraft hydraulic servicing.

Product Overview

The 155S9-12D threads securely onto the open male (bulkhead mounting) half of an Aeroquip 145/155 coupling in the -10 or -12 tube size range, sealing off the internal poppet valve, sealing surfaces, and threads from contamination, moisture, hydraulic fluid residue, and foreign object debris (FOD). It ships as a complete assembly with a size 8 retention chain, keeping the plug captive on the coupling or GSE line for convenient access and preventing loss during active servicing — a key requirement in military and commercial aviation maintenance environments with strict FOD prevention programs. The 155S9-12D is the factory-approved OEM replacement dust plug for MIL-H-5606 and MIL-H-83282 red oil hydraulic coupling applications in the size 12 range. For Skydrol phosphate-ester systems, the equivalent part is the 015567S9-12D.

Key Features

• Size 12 dust plug — fits Aeroquip 145/155 Series coupling halves in -10 and -12 tube sizes
• Protects internal poppet valve, sealing surfaces, and threads from FOD, moisture, and fluid contamination
• Ships as a complete assembly with size 8 retention chain — plug stays tethered during servicing operations
• Compatible with MIL-H-5606 and MIL-H-83282 petroleum-based red oil hydraulic systems
• Factory-approved Eaton Aeroquip OEM replacement — fully interchangeable with fielded 145/155 Series couplings
• Supports FOD prevention programs on the flightline, in maintenance hangars, and at depot level
• Skydrol equivalent: 015567S9-12D (for phosphate-ester system applications)
• Simple thread-on installation — no tools required
• NSN: 4730-01-394-3297 — eligible for government and military procurement

Applications

• Protection of open male coupling halves on high-flow aircraft hydraulic service carts and mule carts
• Flightline FOD prevention during hydraulic system ground servicing of -10 and -12 size circuit connections
• Storage and shipping protection for spare 145/155 Series -10 and -12 coupling halves
• MRO facility hydraulic GSE maintenance and reconditioning programs
• Military aviation maintenance units (AMUs, AGE shops) operating 145/155 Series equipment
• Replacement of lost, worn, or damaged dust plugs on in-service coupling assemblies

Compatible Coupling Halves

The 155S9-12D dust plug fits the following Eaton Aeroquip 145/155 Series coupling halves (size -10 and -12, hydraulic red oil):

• 155S5-10D — Style I, -10 size, hose attaching half
• 155S5-12D — Style I, -12 size, hose attaching half
• 015519S4-10D — Style I, -10 size, bulkhead mounting half
• 015519S4-12D — Style I, -12 size, bulkhead mounting half

Specifications

• Part Number: 155S9-12D
• Accessory Type: Dust Plug Assembly
• Series Compatibility: Aeroquip 145/155 Self-Sealing Couplings
• Plug Size: 12 (fits coupling halves -10 and -12)
• Fluid Compatibility: MIL-H-5606, MIL-H-83282 (Red Oil)
• Chain Assembly: Size 8 retention chain included
• Skydrol Equivalent: 015567S9-12D
• NSN: 4730-01-394-3297
• Manufacturer: Eaton Aerospace (Aeroquip Brand)
• CAGE Code: 00624