What it does when the Wi-Fi drops is the specification that counts · review
Thirty detectors and twenty remotes is the biggest expansion figure on this shelf — and the entry delay the hub tip warns about is one you set yourself.
The conclusion Thirty detectors and twenty remotes, with KERUI hub compatibility so the sensors are not single-sourced — that is the largest and most useful expansion statement on this shelf, and it makes thirty-eight dollars a starting point rather than a dead end. The adjustable entry delay and alarm duration are the other real features. It is Wi-Fi only with no cellular fallback and no published hub battery, which leaves the introduction's two central questions unanswered.
No cellular fallback. No backup battery. No sensor radio protocol.
And four kits on this shelf give none.
Ring, SimpliSafe, eufy and Arlo all say sensors are available separately and publish no ceiling. That is a worse answer than a figure.
Thirty detectors and twenty remotes covers a house, a garage and a workshop on one hub.
And KERUI hub compatibility means the sensors are not locked to one brand’s supply — which for a kit at this price is the difference between a starting point and a dead end.
Which is the setting this shelf’s buying tip singles out.
An entry delay is the grace period between a sensor triggering and the siren sounding, so you can disarm on the way in.
The tip is blunt about the other half: it is also the time it takes to find the hub and unplug it.
Ten seconds or sixty is a real trade, and this is the only kit here that says the delay, the alarm duration and the timers are all adjustable.
Which this shelf’s introduction makes its second test.
Two point four gigahertz, the Tuya app, and nothing else. No cellular radio, no stated hub battery.
A cut line or a pulled plug leaves a local siren that sounds and a phone that hears nothing.
The D1D9 kit on this shelf puts a 4G radio in its hub and charges nothing monthly for it. That is the answer to the same question.
On sale at around $38 on the American Amazon store at the time of checking.
Prices and availability are what Keepa reported on the date this page was updated; both move.
Prices quoted in this text were read on October 8, 2026. The live price is at the top of the page.
| Contents | Six pieces: one WiFi loudspeaker hub, one door and window sensor, one motion sensor, two remote controls and one power plug — itemized, which four kits on this shelf do not do |
|---|---|
| Expansion | Up to 30 wireless detectors and 20 remote controls — stated, and the highest device limit published on this shelf. Ring, SimpliSafe, eufy and Arlo state no limit at all; the Honeywell panel here names four keypads. HOAYVKJ also states compatibility with KERUI hubs, which widens the sensor supply beyond one brand |
| Siren | 120 dB from the hub loudspeaker, stated. It is one of only two decibel figures on this shelf, against SimpliSafe's 100 dB base station |
| Control | Arming and disarming delays, alarm duration and timers are all customisable in the Tuya app — stated. This shelf's buying tip says the entry delay you set is the time it takes to find and unplug the hub, which makes an adjustable delay a security setting rather than a convenience, and this is the only kit here that states it is adjustable |
| Connectivity | 2.4 GHz Wi-Fi through the Tuya app, and nothing else. There is no cellular fallback and nothing is stated about what happens when the broadband drops — which this shelf's introduction calls the second half of what survives a failure |
| Backup power | Not published. The listing says the siren just needs to be plugged into an outlet, with no battery mentioned, so a cut mains is an unanswered question |
| Monitoring | None and no subscription: alerts go to your phone through the app, and door open or closed status can be checked in real time. Self-monitored by design |
| Installation | Pre-programmed before shipping, stated. The siren plugs into an outlet and the sensors fix with adhesive pads or screws, with no wall damage claimed |
| Radio | Not published for the sensors. No frequency and no protocol name, as on every consumer kit on this shelf |
| Amazon reference | B0GWHPSKRT |
| EAN | 0768904902331 |
Because it is the figure that decides whether a cheap kit is a starting point or a dead end. Thirty detectors and twenty remotes is enough for a house, a garage and a workshop on one hub, and HOAYVKJ adds that KERUI hubs are compatible — meaning the sensors are not locked to one brand's supply. Four kits on this shelf say sensors are available separately and publish no ceiling whatever, which is a worse answer than a number. For anything that will grow one sensor at a time, this is the most useful thing on the page.
The page does not say, and that is the gap. This shelf's introduction makes it one of two central tests: whether the hub has a battery when the mains goes, and whether it has a mobile fallback when the broadband drops. This kit is 2.4 GHz Wi-Fi and the Tuya app, with no cellular radio and no stated battery — so a cut line or a cut socket leaves a local siren that still sounds and a phone that hears nothing. The D1D9 kit on this shelf puts a 4G radio in its hub with no monthly fee, which is the answer to the same question.
More than it sounds, and it is the one setting this shelf's buying tip singles out. An entry delay is the grace period between a sensor triggering and the siren sounding, and it exists so you can disarm the system on your way in — but the tip is blunt that it is also the time it takes to find the hub and unplug it. A kit that lets you set that delay to ten seconds rather than sixty, and set the alarm duration separately, lets you tune the trade. This is the only kit on this shelf that states both are adjustable.
Between security devices of the same category and nearby price. Shown: what they all state. A half-filled column says nothing.
| Model | Price | Contents | Siren | Connectivity | Backup power |
|---|---|---|---|---|---|
| HOAYVKJ WiFi alarm system kit, 120 dB siren hub, 6 pieces | $38 | Six pieces: one WiFi loudspeaker hub, one door and window sensor, one motion sensor, two remote controls and one power plug — itemized, which four kits on this shelf do not do | 120 dB from the hub loudspeaker, stated. It is one of only two decibel figures on this shelf, against SimpliSafe's 100 dB base station | 2.4 GHz Wi-Fi through the Tuya app, and nothing else. There is no cellular fallback and nothing is stated about what happens when the broadband drops — which this shelf's introduction calls the second half of what survives a failure | Not published. The listing says the siren just needs to be plugged into an outlet, with no battery mentioned, so a cut mains is an unanswered question |
| HOAYVKJ WiFi alarm system SetD, 120 dB IP65 siren, 4 motion sensors, 6 pieces | $57 | Six pieces: four motion sensor alarms, two remote controls, one WiFi loudspeaker and one power plug — itemized. Note what is absent: there is no door or window contact in the box | 120 dB, stated, from the weatherproof loudspeaker hub | Home Wi-Fi for arming, disarming and real-time alerts from away, plus two remote controls for anyone without the app — stated. No cellular fallback appears | Not published. The hub plugs in and no battery is mentioned |
| D1D9 OCC1 24-piece wireless DIY alarm system, 4G, Wi-Fi and GSM | $110 | 24 pieces, stated as door and window sensors, motion detectors, a remote control and a siren. The individual counts are not broken down, so what the twenty-four pieces are is unverifiable from the page | A siren is listed among the contents with no decibel figure and no location | 4G and Wi-Fi, stated, with a SIM card or Wi-Fi required. This is the only kit in this group whose mobile fallback is hardware rather than a subscription feature — the figure this shelf's introduction puts second | Not published for the hub. The listing states instead that the batteries supplied with the sensors are gifts and are not to be replaced under warranty |
| RenseCum A107F home alarm system, GSM/4G and Wi-Fi, 24 pieces | $129 | 24 pieces, stated, with door and window sensors and motion sensors named and a remote. The individual counts are NOT broken down, which is the same omission as the other large-piece-count kit on this shelf | Not published as a decibel figure. The SOS is stated to trigger the siren instantly and no sound level appears anywhere, where two kits on this shelf publish 100 and 120 dB | 2.4 GHz Wi-Fi together with 2G/4G cellular, with 5G explicitly stated as not supported. A cellular radio in the hub with no subscription is the answer to the question this shelf's introduction puts second — what happens when the broadband drops — and two kits on this shelf have it | Not published. No hub battery and no runtime is stated, which this shelf's introduction puts first |
Details checked on October 8, 2026.
A shed, a garage or a small shop that will grow to a dozen sensors and never pay a subscription
Amazon reports what buyers took in the month before this page was last checked: at least 100.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Specifications: the manufacturer sheet for home security products and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
Hub and siren · expandable · DIY installation · app control · voice assistant compatible
ABUS's Smartvest Pro starter set: the hub and siren of a system designed to be expanded, installable without prior knowledge and operated by app, from a manufacturer whose main business is physical security.
Best for: Someone building a system over time who wants the sensors and the door hardware to come from the same maker.
Wired plug-in keypad sensor hub plus 2 all-in-one sensors · 8 detection functions per sensor: motion, open/close, water leak, freeze, smoke/CO listening, tilt, ambient light · one tap emergency response · SecureLink named with no protocol or range
Two sensors that each do eight jobs — which is a genuinely different answer to a shelf that counts pieces.
Best for: An apartment where two well-placed sensors beat eight single-purpose ones, and leaks matter as much as doors
≈ $150
24 pieces · 4G and Wi-Fi, with a mobile fallback that needs no subscription · SIM card or Wi-Fi required · no monthly fee · batteries described as gifts, not warranted · no siren level, no radio frequency, no sensor breakdown
The only kit here with a mobile fallback that costs nothing monthly — and the only one that disclaims its own batteries.
Best for: A second property or a vacation rental, where nobody will be paying a subscription and 4G is the only reliable link
≈ $110
