Community safety schemes in Rhondda Cynon Taf (RCT) are piloting a new crime-fighting device.
The box can instantly alert other users of potential danger
The AlertBox transmits warning messages to other users within 150 metres at the touch of a button.
The digital box can also be used to transmit requests for help in fires or medical emergencies.
Neighbourhood Watch, crime prevention groups and the police are giving trials to the device in Devon and north London, as well as in south Wales.
When a message is sent from one AlertBox all others on the network bleep instantly and bring up the sender's name, address and phone number.
The box's manufacturers claim it is the only panic button device which can simultaneously alert several people with a single press of a button.
Esther Pype, 82, is trialling the device in Aberdare
In RCT the AlertBoxes have been supplied to an infants school, doctor's surgery and magistrates court.
A community safety group on an estate in Aberdare is also trialling the box, which is around the size of a paperback book.
Carl Harris, area crime watch co-ordinator, said: "We'd like to link it throughout the whole of the estate, so that everybody, maybe every 10 houses, has got one of these boxes.
"If there are 19 or 20 out there, if one person pressed the alarm button, then there are 19 possible people to respond."
Esther Pype, 82, is one of the pensioners piloting the scheme, which aims to reduce fears among the elderly of bogus callers and intruders.
The box can send a range of warnings
She said: "I think for the elderly, it will be very good, especially for the ones that can't get about."
AlertBox's manufacturers said the device was not intended to replace 999 calls in the event of an emergency.
AlertBox managing director, Peter Harris, said: "AlertBox - like Neighbourhood
Watch itself - is not an alternative to emergency services but it does offer
valuable back-up and peace of mind.
"Knowing you just have to press one button to alert your neighbours to a
nuisance caller or suspicious person or to call for help is something that the elderly or those who live alone will really value."