This GSM-BUG at unlimited distance is very easy to use and it stands at a mere 40 x 30 x 10 mm along with its internal rechargeable battery, in fact, make it perfectly suitable for discreet eavesdropping and smart concealing in basically any possible location.
You have to insert the SIM card in its housing and with just one click the GSM bug will be ready for use. So you save a lot of time for installation. To listen it's enought call the Sim number.
The GSM bug has the voice activation sensor too. When its built-in sensor detects a sound with a volume over 60 dB, it will automatically call the preset number, which has been previously stored by sending a remote SMS. It can be programmed from a distance through simple instructions sent via sms.