Eyes can close. Ears never do.
The strobe light is on the same team as us: active protection, the kind the French State already subsidises for tobacconists. It disorients with light, LIMA SHIELD with sound. The difference lies in the sense being targeted, and in what the intruder can do to protect themselves from it.
“You learn quickly on call-outs: a person looks away from a flash, but can do nothing against sound. It is not a question of willpower; it is physiology.” Cédric Fontaine, founder of Lima Groupe, former municipal police officer
Comparison checked in September 2026.
Comparing a strobe light and a sound shield means you have already settled the most important point: you want a system that intervenes during the intrusion. That leaves the questions retailers ask when choosing between them.
The real question to ask of an active system: what can the intruder do to protect themselves from it? This is where light and sound diverge.
A signal of 86 to 138 decibels does not stop at the ear: the acoustic pressure is felt in the skull and the chest. Covering your ears is not enough, and staying exposed is no longer a matter of decision but of reflex.
A flash gives away its own position. Indoors, sound reflecting off the walls makes the LIMA SHIELD source almost impossible to locate: the intruder cannot find the device to go after it, and tamper protection guards against removal.
The signal is modulated several times per second, in frequency and intensity: the brain can neither predict it nor get used to it, a finding established by psychoacoustic research. The effect does not rely on surprise alone.
The two systems in brief. They belong to the same family, active protection, but they do not target the same sense, and the intruder does not have the same means of protecting themselves.
The details, criterion by criterion, built around the only question that determines how well an active system really works: what can the intruder do to escape it?
| Strobe light | LIMA SHIELD | |
|---|---|---|
| Sense targeted | Sight. | Hearing, and the whole body: pressure felt in the skull and the chest. |
| Protecting yourself | Looking away, looking at the floor, closing your eyes. | Covering your ears is not enough: the discomfort and disorientation remain. |
| Locating the source | The flash gives away its own position. | Indoors, reflections make the source almost impossible to locate. |
| Habituation | Relies on visual surprise. | Modulation that prevents habituation (psychoacoustic research). |
| Coverage | Limited to the lit area. | Sound fills the space: up to 100 m² per device, reflections included, with no blind spot. |
| Both together | Compatible: both are triggered from the same installation, and the effects of light and sound combine. | |
The two combine very well, and many installations pair them. The question is which plays the lead role on your premises.
Often the right set-up: LIMA SHIELD as the main system, the strobe light as a visual supplement on the same installation.
Closing your eyes takes a second. Escaping a sound of 86 to 138 decibels, calibrated to the 2 to 5 kHz band where human hearing is most sensitive, is not a matter of will: the avoidance reaction is a brainstem reflex. It is not about the intruder's courage; it is physiology.
No blind spot, no corner left out: distributed evenly and reflected by the walls, the sound covers up to 100 m² per device, and paired devices coordinate beyond that.
A flashing unit tells you where it is. The LIMA SHIELD sound source is almost impossible to locate indoors, and any attempt to tear it off triggers tamper protection: the device protects itself.
A French acoustic deterrent device, winner of the Audience Award at the Nuit de la Sécurité Globale (Républik Group): built-in detection or connected to your existing system, warning beeps, then sound saturation until the flight reflex kicks in. Without contact, without any substance, without confrontation, and it protects even without power or Internet.
Behind the unit: a French startup, co-founders from the army and the police, engineers, some of them formerly at Dassault, nearly €1 million in research and development, prototypes built in Strasbourg, and compliance with European CE standards.
“Derived from military technology adapted for civilian use, this non-lethal acoustic deterrent device integrates with any existing alarm system.” Républik Group, La Nuit de la Sécurité Globale
Tobacconists, jewellers, warehouses, town halls and police stations already feature among our first customers and pre-orders.
LIMA SHIELD costs €2,500 excl. VAT, once, with no subscription or consumables: around 68 cents a day over its 10-year lifespan, against the total cost of a burglary, from around €2,000 to €95,000 depending on the extent of the loss. And we carry the long-term risk: 2-year manufacturer's warranty, battery excluded.
Yes, and it is often the right set-up: both are triggered from the same installation, via dry contact or radio relay. The light adds its visual discomfort, the sound makes the area unbearable.
LIMA SHIELD emits no light: the photosensitivity question does not arise. As for hearing, warning beeps and a delay precede any emission; at a normal distance and with brief exposure, the effects are temporary (discomfort, ringing in the ears), and the emission stops automatically at the end of the set duration.
Yes. For indoor use, no French law or regulation known to date caps the power of an acoustic deterrent device, and LIMA SHIELD belongs to a category distinct from sirens. It is CE compliant, and in the event of an intrusion its use falls within the lawful defence of property (article 122-5 of the French Code pénal).
An unlikely scenario given the element of surprise, but there is an honest answer: even attenuated, the sound remains a physical pressure felt in the skull and the chest. The intruder remains disoriented, unable to communicate and deprived of any useful perception of their surroundings.
LIMA SHIELD is up and running in 5 to 10 minutes, on its own or alongside your current installation. It is produced in limited runs, and is regularly out of stock.
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