According to UL 94 V 0 Notice! To be compliant with EN 54‑24: The loudspeaker must be installed with the back‑box LC3‑CBB. 1438 Bosch Security Systems BV Torenallee 49, 5617BA Eindhoven, The Netherlands 1438-CPD-0336 EN 54-24:2008 Loudspeaker for voice alarm systems...