The extension module allows you to connect additional buttons in push-button panels of Urmet digital systems. It replaces the model 1038/17. 1083/17 is used in the panels of the Sinthesi S2 and Sinthesi Steel stylistic lines. A single expansion module allows you to connect from 1 to 16 buttons. Four expansion modules can be attached to the panel, which allows you to connect 64 buttons. Connections between the modules as well as connections between the module and the push-button panel are made using a dedicated cable.