Two test cable types and grades are recommended and provided by Pico Technology. Both of high quality, with robust construction and stainless steel connectors, the main difference between them is the stability of their propagation velocity and loss characteristic when flexed; that is, the degree to which a measurement could change when the cables are moved or formed to a new position.

Cables are specified in terms of flatness and phase variation at up to 6 GHz when a straight cable is formed as one 360° turn around a 10 cm mandrel. Standard test cables are highly flexible. The premium flex-formcables are also flexible but tend to hold their form until intentionally moved to a new position. This further enhances repeatability for bench measurements at fixed port locations or for test installations.