* At midnight, when the hotel door quietly opens—can you notice? On overseas hotel stays, there are daily posts on social media and travel forums about experiences such as "I felt the door opened while sleeping" or "Cleaning staff entered without notice."
Actually, even if you lock the hotel door, it is not completely secure.
Staff can unlock it with a master key, and the chain lock can be released from outside if a wire is hooked through the gap in the door.
"Locking the door and sleeping" does not guarantee peace of mind.
* Therefore, a "2-layer" system is necessary.
A single door lock cannot alert you if someone forcibly pushes the door open.
A single alarm cannot respond in time if a spare key is used to quietly unlock the door.
The design philosophy of this set is to simultaneously cover these two blind spots.
"2-Layer Defense Set | Blocks both spare keys and forceful entry" — just "locking the door" is insufficient, as hotel staff with a key can quietly unlock it with a spare key.
The chain lock can also be bypassed from outside if a wire is passed through the gap in the door.
This set seals off these blind spots in two stages at the same time.
"Layer 1: Portable Door Lock" — Insert the stainless steel arm into the door frame's keyhole, hook the ABS resin stopper, and it prevents the door from physically opening from outside, whether unlocked with a key, card key, or attempted picking.
Even if unlocked, the arm presses against the door frame, preventing the door from moving.
"Layer 2: Door Wedge Alarm" — When attempting to force the lock and even slightly moving the door, the sensor on the bottom of the wedge detects vibration, immediately triggering an alarm sound and red flashing light.
By combining a lock that "prevents unlocking" and an alarm that "detects forceful entry," the system covers blind spots that cannot be addressed by either alone.
"125dB loud volume + red flashing alarm | Sensitivity adjustable in 3 levels, floor material not an issue" — The door wedge alarm activates simply by inserting it into the gap under the door and switching it on.
If the door moves even slightly, the vibration sensor at the wedge's bottom reacts instantly, activating a 125dB electronic alarm and red flashlights simultaneously.
125dB is comparable to the noise level of a jet engine nearby, reaching even the next room or hallway where other guests are walking.
Even during late-night sleep, it will wake you up and serve as a powerful deterrent to intruders.
Sensitivity can be switched among High, Medium, and Low using the side slide switch.
In High setting, it reacts to even small vibrations, which may cause false alarms in environments with frequent hallway traffic or during nighttime bathroom visits.
It is recommended to switch to Medium or Low according to indoor and outdoor conditions.
The front of the body is equipped with a stainless steel anti-slip plate, ensuring stable installation on flooring such as hardwood, tile, or carpet.
Power is supplied by one 9V battery (sold separately), available at convenience stores or airport shops.
"Tool-free, 3-second setup | Immediate use in hotels, Airbnb, or single-room living" — Installing the door lock is completed in 3 steps.
(1) Insert the stainless steel arm into the door frame's keyhole, (2) close the door, (3) hook the ABS resin stopper onto the arm's hook.
No tools are required, and with practice, installation takes less than 3 seconds.
The alarm is even simpler: just place it inside the door or at the bottom and switch it on to standby mode.
Installation and removal of both items can be completed within 5 minutes after check-in.
It can be used anywhere such as domestic and international business hotels, city hotels, private lodgings (like Airbnb), guesthouses, or any inward-opening door in a private residence.
When leaving, it can be removed in reverse order within 10 seconds, allowing for smooth packing even on busy mornings before checkout.
Note: The door lock is only for inward-opening doors (not suitable for outward-opening, sliding, or folding doors).
Please check the notes section for details.
"Compact and lightweight | Size that can be carried without worrying about LCC weight limits" — The total weight of the set is approximately 100–142g for the door lock plus about 43g for the alarm, totaling up to around 185g.
It is almost the same weight as a typical smartphone (about 180g), making it compact enough to fit in a woman's travel bag or pouch.
The door lock comes with a storage pouch, allowing easy transport without damaging other luggage.
You can carry it without worrying about LCC carry-on limits of 7kg or international flight 10kg restrictions.
By preparing a dedicated small pouch before departure and keeping this set inside, you can develop a habit of always bringing it along on any trip.
It can be used for domestic travel, international personal trips, business trips, backpacking, and any travel style.
Beyond travel, it can be used at home for the front door of a single residence, room doors in shared houses, or hospital rooms during long-term hospitalization—any environment where a third party with a spare key might be present.
"Caution | For inward-opening doors only, batteries sold separately, and check airline carry-on regulations" — Please confirm before purchasing.
"About the door lock" — The portable door lock is only for inward-opening doors.
It cannot be used on outward-opening, sliding, or folding doors.
Since many homes and some hotels in Japan have outward-opening doors, use this mainly for inward-opening doors in overseas hotels or domestic hotels that adopt inward-opening doors.
Be sure to check how the door opens at your accommodation.
"About the alarm battery" — The door wedge alarm requires one 9V battery, which is not included.
Please prepare one at convenience stores, home centers, or electronics stores before departure.
Since it may be difficult to obtain abroad, it is strongly recommended to purchase before leaving Japan.
"Regarding airline carry-on" — Since the door lock includes stainless steel metal parts, carrying it as hand luggage on aircraft may cause issues at security checks in some countries or airlines.
There are reports of confiscation, especially on transit through China.
It is recommended to pack it in checked luggage.
2026/06/29 11:20:03#b857ccbdc80eeec1aa645409201ebeacf2a99764
| Product # | 2BRNKJ3NN2 |
|---|---|
| Weight | 250 g |
| Specifications |
色: ブラック |
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