One Tech Intl' Co.,LTD

High quality, High technology,Innovative products ,Fast shipping ,Professional Service,
Quick Menu

OTP-GSM88 GSM spot monitor with lion battery

GSM Listening device



1.       Voice active monitoring with super mini dimension.

2.       Built in adjustable sensitivity voice active microphone.

3.       Built in High sensitivity monitoring amplifier microphone

4.       Built in phone number filter function, other phone will not allowed to monitoring.

5.       Can used SMS to set active or deactivate sound active mode.

6.       Built in shock alert active function, will call and send SMS when detect shock alert.

7.       Easy to operate, just install SIM card and SMS setting for all function modes

8.       Built in earphone jack, allowed to communicate as spy device.

9.       Built in rechargeable polymer LIION battery, with capacity up to 550mA

10.   New less power chip, with standby mode up to 72 hours and 2 hours monitoring mode.

11.   Built in charger circuit allowed using in charge mode.


Product structure:




GSM tri band module

900 /1800 /1900 MHz

Voice sensitive


Standby power consumption


Working power consumption



3.7V 550mA

Charger power

5VDC at 500mA





Filter mode

4 sensitivity voice filter

Alert mode

3 SMS number&1 calling number

Control mode

SMS control


With shock alert mode can used for home safety GSM alarm security system.
With mini dimension allowed us to put in hidden place,
to protect you for safety home.
Can put in briefcase or bag to protect from someone.






Power Charger and GSM monitor.



User's Manual Download