The mains powered wired doorchime is one of a range of stylish easy-to-fit GreenBrook door chimes designed to compliment nay home. This door bell set includes a built in transformer, no batteries required. Can be used with any wired Bell push (DP types), including ornate & lit ones. Makes a traditional dual tone ding-dong sound. Bell push and wood screws supplied. Chime unit = 17cm x 10cm x 4.5cm (depth) Bell push unit - 5.5cm x 2.5cm x 1.5cm (depth) Was DHT01AC - now DHT01ANC