To complete the Italian In-Kind contribution to the ESS SRF Linac, we are working on the qualification of the last eight missing cavities. To achieve this, we are proceeding with reprocessing of not yet qualified cavities and, as a mitigation, we are constructing at the vendor four more cavities. In this paper, we report on the actual status of both of these activities with the most recent results.

The VSR DEMO SRF 1.5 GHz cavities require a large tuning range of 1 MHz to allow for the desired operation, including a cavity parking mode. The tuning system composed of blade tuner, stepper motor, release mecha-nism, and pre-loaded piezos installed into frames features mostly components already validated and used for other applications. However, the operational demands for the VSR application require adaptation of some of the com-ponents and testing to assess performance during aug-mented operation. Here the results of all component tests, most performed at cryogenic temperature, are presented.