Meichoon Bike Alarm Wireless Vibration Motion Sensor with Remote Control Anti-Theft Burglar for Bicycle E-Bike Motorcycle Scooter Cart Trailer Equipment Fence 110db Super Loud

This alarm is extremely disappointing. As soon as I opened it to insert the batteries, one of the battery compartments came loose and flew out. Furthermore, there was no beeping sound when I attempted to activate it. I recommend not wasting your money on this product; instead, consider investing in a higher-quality alternative.

Let's get the downside out of the way first. The battery cover is a tough to remove and with the level of pressure required I can imagine the latch sections will snap eventually. Although you're not going to be opening regularly once the batteries are installed so that's probably a moot point. Additionally the remote control unit looks and feels very cheaply made.As for functionality, the unit takes 2 AAA batteries (not supplied) and it's LOUD. Be warned, when installing the batteries be ready to cover your ears. This thing goes off like one of those smoke detectors which has people kneeling on the floor clutching their ears in pain! It's a serious volume, and with a seriously piercing sound, which is absolutely perfect for its given job.So 5 stars for the functionality but one star knocked off for the construction.All in all it's a decent little motion sensor.

This set has an alarm that requires 2xAA batteries and a remote control using button cells (already fitted). You get two small sicky pads to go on the back of the alarm to fix it to a flat surface.The first thing I noticed was that the battery cover on the alarm is incredibly loose. Some other reviewers say theirs are tight, so manufacturing isn't that consistent. The cover is also not waterproof (if it even stayed on) so not sure where I can put it on my bike with confidence it will stay dry.There aren't any other fixing mounts to use cable ties or anything, so you really are limited to a flat surface where you can also get to the battery cover (if it's still on when you come to change them).The remote has three functions;1. Arm / Disarm the alarm2. Make a doorbell noise to locate the alarm/bike3. Set off the alarm manually.The alarm is quite loud, usual smoke alarm volume but ignore reviews with a sound meter - the readings are supposed to be at 1m away (dB/m). Certainly enough to hear your bike being moved from a fair distance, or if left outside a cafe or something.I would be worth 4 stars if the battery cover wasn't loose, and maybe even 5 if it had better mounting points. It's fairly sensitive to react though.