Part Number 100A Grothe Croma 100A Electronic Wired Doorchime A robust and sophisticated wired wall mounted doorbell powered by either batteries, or an external transformer. A robust and sophisticated wired wall mounted doorbell powered by batteries or an external transformer. Supplied with 17 CD quality sounds (listen to the sound samples below by clicking on the sound icon). Loudness up to 86dB, with rotating volume control Front door / back door operation, with alternate chime sounds for each bell push button Powered via an 12 V A/C mains transformer (not included), (Model E3538S) or batteries. Silence button to allow the chime to be silenced conveniently. Convenient front opening panel for sound choice and adjustment Extremely robust German design. [ Click to Enlarge ] Sound Samples (Click Speaker Icon) 3 Tone 2 Tone 2 Tone x 2 Gong 3 Westminster 9 Tone Telephone Alarm Gong 2 Flute Gong, & Bark Symbol Melody 8 Tone Beethoven Welcome Dog Bark To Download the pdf of the manual click here :[ Croma 100A Manual.pdf ] Specifications Dimensions - 164mm x 190mm x 51mm. (6.5" x 7.5" X 2" approx). Colour, black sides with clear perspex front on silvered background. Chime can be powered by an 12V a/c, 1.5 amp mains transformer (E3538S) (not included). For battery use (4x1.5V, type LR14/C, alkaline batteries) Front door - back dooroperation , with second bell push button. Sound Level dB@1M, 86db. Special alarm function with emergency call tone for special situations No of polyphonic tones available, 17. Mute function. Please note, this doorbell is not suitable for use with illuminated bell push buttons Operating temperature range for all chimes is 5°C to + 40°C. Options Mains Transformer: Click Here: [ E3538S ] See choice of bell pushes Here : [ Bell Pushes ]