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Upgraded Bike Alarm Waterproof with Remote, Electric Bicycle Door Burglar Alarm,eBike Anti Theft 113dB Loud, Adjustable Sensitivity, Scooter Accessories Vibration Sensors

  • Based on 1,749 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Friday, Aug 1
Order within 8 hours and 20 minutes
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Features

  • SUPER LOUD 113DB - Vibration triggering loud alarm to scare away thieves.Prevent Robbery and Door Prying.
  • ADJUSTABLE SENSITIVITY - High sensitive vibration sensor,7 level from gentle touch to push or beat.Adjustable volume.
  • EASY INSTALLATION FIRM AND WATERPROOF - No wiring, no screw,provide super strong adhesive tapes and cable tie for installation.IP55 waterproof design, can use for outdoor.
  • MINI SIZE - 3.7"*1.6"*0.8" exquisite and compact design, easy to hide and install, suitable for bike/car/motorcycle/door/moped anti-theft alarm.

Brand: HENDUN


Power Source: Battery Powered


Number of Batteries: 3 AAA batteries required.


Noise Level: 113 dB


Mounting Type: Surface


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 3.7 x 1.8 x 0.6 inches; 4.48 ounces


Item model number ‏ : ‎ KS-SF22R


Batteries ‏ : ‎ 3 AAA batteries required.


Date First Available ‏ : ‎ November 19, 2018


Manufacturer ‏ : ‎ Changzhou Hengdun Electronic Technology Co Ltd


Country of Origin ‏ : ‎ China


Customer Reviews: 4.4 4.4 out of 5 stars 1,749 ratings


Maximum Range: ‎20 Meters, 10 Meters


UPC: ‎664248633569


Manufacturer: ‎Changzhou Hengdun Electronic Technology Co Ltd


Item Weight: ‎4.5 ounces


Product Dimensions: ‎3.7 x 1.8 x 0.6 inches


Country of Origin: ‎China


Item model number: ‎KS-SF22R


Batteries: ‎3 AAA batteries required.


Is Discontinued By Manufacturer: ‎No


Wireless Remote: ‎Yes


Date First Available: November 19, 2018


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Aug 1

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Makeshift car alarm 🚨
I was looking for creative ways to deter whoever keeps syphoning all my gas. Zip tied it to my gas cap so when they open it the alarm goes off. Super happy with how loud this thing is- I’m off grid and currently using a generator so I had to get something I can hear over the background noise. I can hear it all the way from my bed- love it so much I’ll be getting a couple more 👀 ... show more
Reviewed in the United States on May 21, 2025 by Tsay

  • Loud and proud
Love it! This is the second one I bought. It IS really loud and actually has a really good range. I highly recommend this
Reviewed in the United States on June 1, 2025 by Joshua Sickler

  • Exactly as described and depicted. Decent alarm.
Seems many of the bike alarms look identical, so you need to pick seller carefully, hoping reviews and luck help. At least that's how I felt. Anyway, roll of the dice, and feel I got lucky. This alarm is apparently the latest updated version that's being sold. The 'fob' is bit gaudy, but I think the placement of buttons allows less button hitting errors. Size is fine, actually very acceptable. I used my own zip straps to affix the alarm unit on the seat post, in the vertical position. if you do the same, be sure you put the access screw on the bottom, so you can remove the casing to replace batteries. Otherwise you'll need to remove the zip strips, and then go through process of attaching it again. But, that might not be a bad idea, since you would be refreshing that aspect of attachment. Speaking of the locking screw and access to the batteries, I want to note that the initial attempt to open the case is not easy. Using the 'guitar pick' pretty much mangled the pick. Eventually, the case did disengage from the bottom, but it was a chore. Especially when you're being careful not to break or damage the product. Btw, the screw, one you get it a bit loosened, unscrews easily. Getting the case open, to remove the plastic tab (which obstructs the battery to keep them fresh until you set it up) was perhaps the most difficult part of installing the product. Which is a positive. You scan your bike to consider ideal location. I would not advise hiding it under the seat, because being in an enclosed area might limit the volume of the alarm. The brief instruction manual states that it should in an open area for optimum alarm protection. I tested the sensitivity of the unit in a vertical and horizontal position, and horizontal seemed slightly more sensitive. However, for safety and aesthetics, I affixed it in a vertical orientation. After zip locking it in place, I used the remote to activate the alarm. I jostled the bike a little..no alarm. Moved it with a bit more motion and it activated. I did not alter the sensitivity, using the default which is supposedly set to the most sensitive setting. I could not set the alarm to my choice of alarm type. Seems it rotates to the next alarm sound after activation. The included user guide/manual is sorely lacking in information/directions. I did notice that changing sensitivity is a series of button presses, which at the moment was too much hassle. Just hope it was in fact set to the default sensitivity mode (again, supposedly most sensitive). This was one of the lower priced of the identical models, with Prime shipping. I felt It was a good bargain, and the alarm met my expectations. Attached are photos to show real world images, with a ruler for size reference. Also, a picture of the alarm affixed to the bike seat post, in vertical position. Decent alarm, at good price. I view it as a moderately high level recommendation. ... show more
Reviewed in the United States on July 11, 2020 by Gnemik Gnemik

  • Great little deterrent and loud as can be!
Fantastic addition to my E-bike. It definitely helps me keep piece of mind when chaining it up somewhere or even while it’s stored in my screened in porch. It is super sensitive. Just a couple of times I’ve tried opening my pannier bags without turning it off and it went off! It’s small enough to not be noticeable and is a great investment to give me extra security to protect my bike. ... show more
Reviewed in the United States on April 22, 2025 by Brian W Barker

  • Small and packs a punch!
This product is pretty small and convenient to use with the remote. We are using it as a catalytic converter theft deterrent. The provided alarm with the car is not sensitive enough to go off if something is cut out from the bottom of the vehicle (ask me how we know). So we attached this to the back of the frame and the muffler/exhaust system on our vehicle. Due to the proximity to the very hot exhaust system, we swapped out the provided plastic zip ties for 16 gauge galvanized steel wire and covered the back and sides with pipe insulation foam and a couple of layers of thick tin foil. (Foam, high temp glue, and wire from the local big-box store). It hangs from the bottom so that it moves freely and it doesn't look the prettiest, but you can't see it unless you crawl all the way under the car. The speaker is aimed at the ground for maximum sound reflection. Sensitivity The highest sensitivity setting works great. If you so much as tap/touch the exhaust system it sets the whole thing off. (the exhaust system is connected to the frame with its own suspension system so touching it anywhere shakes the whole thing). There is first a loud warning chirp and if you touch it again within a short amount of time it will go off for roughly 30 seconds. (if you continue to cause it to move, it will continue to go off). So if it is accidentally set off it will stop on its own without you using the remote to turn it off, which was a huge plus for me. For being so small it's quite loud. From reading the other reviews we did decide to swap the provided batteries out with higher quality ones. We will not be using the provided SOS signal because it is not used on a back, but we didn't have to worry because it comes programmed without that being turned on. ... show more
Reviewed in the United States on October 8, 2022 by Tim Bogisch Tim Bogisch

  • Good features, perfect performance. Dig deeper for programming options
Works great. Don't forget to fully explore the finer programming like type of alarm, loudness, and shake sensitivity. This has done everything we needed. Use it on a mobility scooter that we have to sometimes leave out of sight.
Reviewed in the United States on April 13, 2025 by KA

  • Needs more Oomph
It operates as advertised but volume not enough to do the job.
Reviewed in the United States on March 24, 2025 by Pete W.

  • Great Price
Wow this is an AWSUM unit works better than I hoped it would SUPER LOUD and sensitive.
Reviewed in the United States on March 20, 2025 by ki0ad

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