Check the listing for details. DeltaBell External Sounder Module Peizeo 104dBA. NO BACKLIGHT - BLUE (AE2MOD). Color: Blue, Condition: New. Listed at 32.86 USD. The Deltabell PLUS provides light to cover to provide around the clock visual deterrent A number of engineer friendly features; the unique levelling mechanism and modular components Fully backlit - When used with backplate base of the Deltabell Plus is backlit constantly. Piezo sounders with high decibel output - Belle: 118dBa. Decibell E/ Deltabell E / Deltabell Plus: 104dBA. Positive/Negative Trigger inputs - Can be connected to any output that is positive applied Universal triggering inputs - Can be connected to any output on a manufacturers control panel, Supplied with battery - Complete with a backup battery so that even in the event of an intruder sabotage, Siren cut-off timer - The cut off timer is defaulted to 15 minutes to meet industry regulations. Engineer hold off facility -.