Use the valve replacement kit to replace valve positioners on digital manifolds from Testo. Particularly useful: you can replace the valve positioners yourself – directly on site.
Immediate valve positioner replacement on site
Valve replacement kit for two valve positioners
Compatible with testo 549, testo 550, testo 557, testo 570, testo 550i, testo 550s, and testo 557s Digital Manifolds