This two-way GSM audio device alerts you when it detects sounds in its vicinity. Simply insert a GSM SIM card and program it to your desired phone number for callback. The device features a built-in microphone with a range of up to 7 meters, allowing you to monitor environments remotely. Key features: - Call the device to listen in on surrounding audio in real time - Device automatically calls you when sound is detected - Tri-band GSM compatibility (850MHz, 900MHz, 1800MHz, 1900MHz) - Built-in 400 mAh rechargeable lithium-ion battery - Voice-activated mode provides 58 days of continuous operation - Compact design with dimensions of 4.3 x 3.2 x 1.4 cm - USB charging cable included for convenient recharging Package includes: 1 x Audio device 1 x Charging cable 1 x User instructions Note: This product is intended for legal use only. It is the responsibility of the purchaser to ensure compliance with all applicable laws and regulations regarding the import, possession, and use of this device. The seller assumes no liability for any unauthorized use or legal violations. This device is not intended for use in violation of privacy laws or for any illegal surveillance activities.