The fit starts with the model

A component can look right and still have the wrong interface. Make a record before comparing listings.

1. Identify the complete knife

Record the manufacturer, full model number and version. Keep 535 and 533, 940 and 945, and Para 3 standard and Lightweight entries separate until specific evidence supports a shared part.

2. Record the construction

Note original or aftermarket scales, liners, clip position and previous modifications. A statement about the original handle does not automatically cover a changed handle.

3. Measure the relevant interface

For screws, record thread, usable length and head geometry. For clips, record mounting geometry and clearance. For pivot parts, record the relevant diameters and thickness. Do not fill a field with a visual estimate.

4. Confirm the package

Count the components in the actual selected retail specification. A photograph showing several colors or loose hardware does not establish the contents of one order.

5. Separate the checks

6. Resolve uncertainty before use

When a specification or functional result is missing, keep it unresolved. Seek the manufacturer’s guidance or qualified service where the component affects safe operation.