https://www.doorbird.com/downloads/datasheet_d2104v_flush_en.pdf
Doorbird Intercom D2104V/D2105V/D2106V Flush-mounting housing (Backbox)
$200.68
Stainless Steel V2A
(GTIN/EAN: 4260423867505, P/n: 423867505)
Fits only D2104V/D2105V/D2106V EKEY IP Video Door Stations