FF Series

Flat face couplers made to the ISO 16028 Standard

The FF Series flat face couplers are AKJia’s flagship products, known globally for their leak-free performance in high-pressure pulse. The preferred choice for many global OEMs.

FF Series couplings are designed for use in excavator hammer circuits and other applications involving high-pressure pulses. widely used in Construction plants, mobile equipment, general industrial, nuclear, mining, and agricultural. FF Series couplings are suitable for applications involving dusty or dirty environments and where oil loss on disconnection cannot be tolerated.


  • Carbon steel with trivalent plating as default
  • Carbon steel with zinc-nickel plating option (500 hours with no red rust in salt spray tests
  • Fitted with Nitrile seals – NBR (Viton seals – FKM available)
  • Also available in AISI 304 and AISI 316 stainless steel (See FFS Series)
Datasheet Inquiry
FF Series Flat Face Quick Couplings ISO 16028

Online Shop For Personal Users or Samples

Personal users can buy the products in stock or business customers can buy them for samples. Register your product for 1-year warranty.


  • Safety locking sleeve fitted as standard to prevent accidental disconnection
  • Flat faces are easily wiped clean
  • Minimal inclusion of air and contaminants during connection
  • Flat face design prevents fluid loss during disconnection
  • Bidirectional flow


  • High pressure pulse applications
  • Hammer circuits
  • Leak free environments
  • Construction plant
  • Mobile equipment,
  • General industrial
  • Agricultural
  • Skid steer loaders
FF Series Dimensions Flat face quick couplings


The flat face quick coupling conforms to the ISO16028 standard, and ISO16028 specifies the size requirements for the connection part of the flat face quick disconnect coupling. All quick couplings that meet this standard can be interchangeable with each other. Users can choose between different brands of quick couplings, which can be interchangeable with each other at half-to-half.

ISO 16028 -2023

Available Seals and Temperature Range

All carbon steel products have Nitrile Butadiene Rubber (NBR) seals fitted as standard. All stainless steel products have Fluoro-elastomer Rubber (Viton®) (FKM) seals fitted as standard. Special seal materials are available on request.

Abbreviation Trade Name Chemical Name Min. Temp Max. Temp
NBR, XNBR Chemigum®,  Hycar8,  Breon®,  Butakon®, Butacril®, Buna-N®, Perbunan®, Paracril®, Krynac®, Europrene-N®, Nipol® Nitrile Butadiene Rubber
Carboxylated Nitrile Rubber
-40ºC (-40ºF) 106ºC (223ºF)
FKM(FPM) Dai-el®, Fluorel®, Tecnoflon®, Viton® Fluoro-elastomer Rubber -20ºC (-4ºF) 200ºC (392ºF)
EPR, EPDM Buna-AP®, Dufral®, Epsyn®, Nordel®, Epcar8, Keltan®, Royalene®, Polysar-EPDM® Ethylene Propylene Copolymer
Ethylene Propylene Terpolymer
-50ºC (-58ºF) 120ºC (248ºF)
FVMQ Silastic 1S®, FSE® Fluorosilicone Rubber -65ºC (-85ºF) 170ºC (338ºF)
FFKM Perlast®, Kalrez®, Chemraz®, Kaflon® Perfluoroelastomer -25ºC (-13ºF) 300ºC (572ºF)