The world’s first adjustable external backpack frame

One299 was designed to meet the changing needs of the Australian Defence Force, by providing a high-load backpack frame that is adjustable to correctly fit the back of 1-percentile to 99-percentile female and male users. Through extensive strength testing, anthropometric analysis and iterative load simulation, Cobalt was able to meet and exceed military expectations and outperform existing fixed-size frames.

In addition to size adjustability, a key element of ONE299 is the patented lumbar area which conforms to the contour of the wearer’s back. This allows for superior ergonomic fit as well as increased load.

The use of a correctly fitting frame reduces the potential for back injury, and the One299 frame offers this to all wearers regardless of size. Its high strength and adjustable nature also opens up new opportunities for load carriage configuration, allowing both frame and the backpack to be adjusted and configured to suit alternate load carriage scenarios.

In excess of 27,000 frames have been deployed in the Australian Defence Force, with additional interest from international military groups and adventure sectors proving a great commercial outcome.


  • Fit users with 1-99 percentile back lengths
  • Meet or exceed metrics of current leading external pack frames
  • Compatible with past and future pack & harness systems


  • 2 x single high-strength polymer mouldings
  • 3D contouring to conform to all body shapes & sizes
  • Integrated adjustment & locking mechanism
  • Local manufacture minimising transport costs & accelerating manufacturing time


  • Anthropometric analysis and application
  • Industrial Design
  • Engineering, testing and analysis
  • Tooling management liaison
  • Marketing assistance
  • CG visualisation


  • Libby Christmas
  • Marcus Krigsman
  • Andrew Fanning
  • Graeme Marshall
  • James Hayes
  • Rob Cuzner
  • Chris Morrish

Iterative FEA and testing for optimised performance

In-depth analysis of use scenarios and user anthropometry formed the basis for the design, while iterative testing and simulated analysis (FEA) provided a detailed understanding of performance under load. These functional targets were achieved within a compressed development program, with design and engineering teams working in partnership with local manufacturers to ensure the client’s performance and commercial targets were met.

Finite Element Analysis (FEA) was used extensively throughout this project, allowing the design and engineering team to compare the design to real life testing.

We at Cobalt were also able to refine details to achieve maximum strength in excess of 80kg working load, while also improving user comfort through specifically targeted flex areas. As part of an iterative process, this simulation led to an end result optimised for strength, weight, manufacturability and user comfort. It also achieved the previously unrealised universal anthropometric and ergonomic targets. Extensive in-house physical testing and Australian Defence Force field trials provided input and feedback during development and validated strength, comfort and usability outcomes of the final product.

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