90 dB Window Door Sensors

A loud 90dB siren triggers the instant a window or door is opened — no tools, no wiring, no installation headaches. Each pack includes two magnetic sensors that mount with adhesive tape and run on included batteries, so you can have multiple entry points protected in minutes. The magnetic design means any separation between the two sensor halves — whether from opening or forced entry — triggers the alarm immediately. Works on windows, doors, and sliding glass doors.

Window and Door Alarm Sensor Features and Specs

• 90dB siren: Triggers instantly when the magnetic sensor halves separate — loud enough to alert from another room and deter intruders
• Two units included: Cover two entry points with one purchase
• Magnetic design: One half mounts to the frame, the other to the door or window — alarm triggers when they separate
• Adhesive tape installation: Peel and stick to any surface — no drilling, no screws, no tools
• ON/OFF switch: Disable when opening intentionally without removing the sensor
• 3 LR44 batteries per unit included: Both units ready to use out of the box
• Compact size: 2½" x 1¾" x ¾" — unobtrusive on any window or door frame
• One-year warranty

Installation takes under a minute per unit — peel the adhesive backing, attach one half to the door or window frame and the other half to the door or window itself, aligned so both halves sit flush when closed. Switch it on and it's armed. The ON/OFF switch lets you open the protected entry point without triggering the alarm when you need access — no need to remove or reposition the sensor. A practical choice for renters who can't drill, homeowners who want quick coverage on secondary entry points, and travelers securing hotel rooms or vacation rentals.

Magnetic Window and Door Sensor Alarms — Entry Point Coverage Strategy

Two units cover the two most common entry points in most homes — a front door and a back door, or a door and a sliding glass door. For apartments and smaller spaces, two sensors cover every exterior entry point without additional purchases. For larger homes with multiple windows and doors, additional units extend coverage systematically — starting with ground floor windows and rear entry doors that aren't visible from the street. The adhesive mount means sensors can be repositioned if an entry point changes or if you move — the tape leaves minimal residue on most surfaces. For entry points where you want detection before the door opens rather than at the moment of opening, a door guard vibration alarm detects handle contact before any separation occurs.

Are window alarm sensors effective?

For entry-point detection, yes. The magnetic design triggers the moment the two halves separate — any opening of the door or window, whether intentional or forced, activates the 90dB siren immediately. The alarm doesn't require motion in the room or a specific entry angle — separation of the magnets is the only trigger condition. The 90dB output is comparable to a smoke alarm and loud enough to be heard from another room in a standard home. These work best as a first layer of detection alongside other security measures rather than as a standalone system — the alarm alerts you and deters the intruder but doesn't prevent physical entry the way a door brace or wedge does.

Will the adhesive hold the sensor in place long term?

The included adhesive tape holds reliably on smooth painted surfaces, metal frames, and most standard door and window materials. On textured surfaces, rough wood, or surfaces with residue from previous adhesive, the bond may be weaker — cleaning the surface before application and pressing firmly for 30 seconds improves adhesion on any surface type. The sensors are lightweight enough that the adhesive holds well in normal indoor conditions. In high-humidity environments like bathrooms or near exterior doors exposed to temperature swings, adhesive performance can degrade over time. For those locations, a small amount of additional adhesive or mounting tape can supplement the included backing if needed after initial installation.