All GPS tracker will lost signal for the tracking position.
Built in battery need any additional power.
Jam only GPS signal not include GSM signal.
Easy to operate.

Specifications:
Working band: 1575 MHz (wide band)
Working time: 3-4hours
Charger time: 1-2hours
Coverage area: 5-20 M Radius.
Power consumption: 250mW
Charge voltage: 5-6VDC
Dimension: 58x45x18 mm
Antenna length: 77 mm
Li-ion battery: 3.7V 750mA

The Complete Set Includes:
1. PORTABLE GPS JAMMER X1
2. Travel Charger X1
3. Car charger X1