Dimensional specifications

In FDA's guidance on changes to 510(k)-cleared devices, a change in dimensions is assessed for whether it could significantly affect safety or effectiveness. Many small dimensional changes do not need a new 510(k), but the decision and its rationale should be documented.

The physical size and shape of the device. Such specifications may include the length, width, thickness, or diameter of a device, as well as the location of a part or component of the device.

FDA guidance: Deciding When to Submit a 510(k) for a Change to an Existing Device (October 2017), Appendix C, Significant Terminology