Feature 1Easily mounted by adhesive, just need to peel and stick. 2Super loud 90 dB alarm, you will not miss it. 3Magnetic sensor switch to detect entry protecting your home or office whether you are in or out. 4Super environmental suitability and stability, enjoying hard-wearing quality. 5Dustproof and insect prevention,long service life of it.Easily mounted by adhesive tape to window or door. Magnetic sensor switch detects entry protecting your home or office where you are in or out,suitable for families, apartments, mobile homes, apartments, office buildings, hotel rooms, garages,the ideal entrance warning! Features: Easily mounted by adhesive, just need to peel and stick. Super loud 90 dB alarm, you will not miss it. Super environmental suitability and stability, enjoying hard-wearing quality. Dustproof and insect prevention,long service life of it. Magnetic sensor switch to detect entry protecting your home or office whether you are in or out. Warning door / window sticker is supplied free in package. Operated by 3pcs of 1. 5V LR44 / AG 13 button cell ( included ), ultra-long standby. Specifications: Sensor Type: Alarm Alarm Type: Sound Material: Plastic Color: White Size (L * W * H): 6.5 * 3.1 * 2cm / 2.6 * 1.2 * 0.8in Package Weight: 34g / 1.2oz Package List: 1 * Magnetic Sensor 1 * Magnetic Bar 3 * LR44 button batteries