KAJA · Sourcing Guide
Footwear development can begin with an existing sole model or with a new sole design. The useful question is which route fits your design requirements, size list and development scope. An existing model can give your team a defined starting point; a new design requires a separate review of shape, construction and tooling.
KAJA supports both existing sole selection and custom development from drawings or samples. This guide outlines the information to review before choosing a route.
Start with the Parts of the Design That Must Stay Fixed
List the requirements your project cannot change. These may include the sole profile, tread pattern, molded logo, upper interface or size range. Separate those requirements from color and finish preferences that could be adjusted around an existing model.
This makes it easier to compare an available sole with the intended design. A style that looks similar in a photograph still needs to be reviewed against the upper and last used by your team.
When an Existing Model Is Worth Reviewing
An existing model is a useful starting point when its construction, shape and developed sizes match your project closely enough to assess through sampling. Check the actual developed size list and available options on the product page.
Colors and hardness can be adjusted through formulation. Painted details and other offered finishes should be confirmed for the specific model. Selecting an existing sole does not remove the need to check the complete specification and compatibility with your footwear construction.
When New Tooling Needs to Be Discussed
Changes to shape, tread patterns, molded logos or sizes beyond existing tooling require new molds. If those elements are central to the collection, send drawings, a technical specification or a physical sample for custom development review.
The proposal should define the construction, agreed size list, tooling scope, sample arrangements and costs. A new design does not begin with an assumed ready-made mold range; these details need to be agreed for the project.
Compare the Two Routes
| Review point | Existing model | Custom development |
|---|---|---|
| Starting point | An available sole style and its developed sizes. | Drawings, specifications or a reference sample. |
| Shape and tread | Review compatibility with the existing design. | Define the new design and tooling scope. |
| Sizes | Check the model’s actual mold list. | Agree the sizes to develop and tool. |
| Appearance | Confirm available colors and finish options. | Review appearance together with materials and tooling. |
| Samples | Existing style samples are available; freight is paid by the customer. | Tooling and sampling arrangements are agreed separately. |
Treat Size Development Separately from Size Labels
KAJA accepts size development requests within EU 22–46. That range describes requests we can discuss, not a promise that each sole already has every mold in the range. The size list of a selected model remains the starting point for an existing-style inquiry.
Ask about any missing sizes before approving the development scope. Include the upper and last information needed for fit review rather than relying on a size label alone.
Use Sampling to Confirm the Proposed Route
Review samples for appearance, selected construction and compatibility with the intended footwear. Free samples of existing KAJA sole styles are available, with shipping paid by the customer. For a new design, mold costs, samples and schedule are agreed for the project.
If the project has performance targets, state them during development. Customers arrange testing, and KAJA uses their feedback to refine formulations toward the agreed targets. The specification should be confirmed before bulk production.
Send a Clear Development Brief
Send the reference style or drawings, required sizes, colors, logo requirements and estimated quantity. Explain which design elements are fixed and which may be reviewed around an existing model.
Explore KAJA shoe soles, email ken@cnkaja.com, or discuss your project with Ken.