The Byron Smartwares BY212 Wireless Port and Plug-In Chime Kit has a 100m range, and a chime with 6 sounds. Over a million self-learning codes. Will keep the code even when the chime unit is unplugged and then re-plugged in. 80-85dB rating depending on the sound.
The portable chime requires 3 x AA batteries (NOT included).
The push requires 1 x 23A battery (included).