Deta C3504 Mains Voltage Door Chime with Built in Transformer Black/White Push by Amazon.co.uk

• Traditional mechanical "ding-dong" type chime (not electronic)

• Built in transformer (no batteries to change)

• Chime sound output 80dB(A) @ 3m. Bell push included, complete with white and black interchangeable fascias

• Connections located bottom of unit. CE approved

• dIMENSIONS: Chime: 128mm tall x 128mm wide x 44mm deep. Fixing centres 100mm vertical (see picture 2); Push: 58mm tall x 29mm wide x 15mm deep. Fixing centres 44mm vertical