Frame for installation on the surface 3 modules. No other accessories are needed for surface installation of the intercom. When installing on a glass or uneven surface we recommend you use a backplate 3 Module Suitable for IP Verso LTE Verso Surface Mount Front Frame for AXIS Verso Door Intercom Used with either a Verso Basic Main Unit 1 additional Module or with 3 x Additional Function Modules. Finished in Brushed Steel Stylish robust Modular Door Intercom system component