The ACR Firefly PRO Waterbug is a SOLAS-approved strobe light that turns on automatically as soon as it becomes submerged. 41 candela, visible for over 4.8 kilometers, more than 56 hours of operating time. Four modes.
Turns on automatically when you are in the water, even if you can no longer do anything yourself
The ACR Firefly PRO Waterbug is the same strobe as the Firefly PRO, but with an additional feature that makes a big difference: water activation. As soon as the light is submerged, it turns on automatically. You don't have to do anything, which is exactly the point if you are in cold water with stiff hands, or worse, unconscious.
For this purpose, this model has a fourth mode: the armed mode. If you set the light to this, it waits until it touches water. The other three modes are the same as on the standard Firefly PRO: bright strobe, SOS pattern, and steady-on for the final stage of the rescue.
The performance is identical. Wide-beam LEDs provide a 360-degree beam with 41 candela, visible for over 4.8 kilometers. The light is cool white without a yellow tint, which carries further over water. On AA lithium batteries, it flashes for more than 56 hours, over 48 hours longer than required by SOLAS and the US Coast Guard. The housing is built to military specifications and has been factory-tested to a depth of approximately ten meters.
Why choose the Firefly PRO Waterbug?
-
Turns on automatically in water: you don't have to do anything, even if you are incapacitated
-
Armed mode: set the light to armed and it waits until it gets wet
-
More than 56 hours of flashing: over 48 hours longer than SOLAS and USCG requirements
-
360-degree visibility: wide-beam LEDs, 41 candela, visible for over 4.8 kilometers
-
Four modes: armed, strobe, SOS pattern, and steady-on
-
Rugged housing: military specification, tested to approximately ten meters
Who is this product for?
This is the version you should attach to a life jacket. Precisely because you might not be able to do anything in an emergency, a light that turns itself on is the safer choice. Suitable for professional shipping and fishing where SOLAS lighting is mandatory, and equally for pleasure boating, rowers, kayakers, and water sports enthusiasts on inland waters. If you prefer to determine for yourself when the light turns on, the standard Firefly PRO is more suitable.
What are the benefits for you?
-
Works if you can't do anything: water activation requires no action
-
You will be seen in the dark: without a light, a person in the water is virtually unfindable
-
Two nights of light: more than 56 hours of flashing on one set of batteries
-
Manual control when possible: manual switching to SOS or steady-on remains possible
-
Meets requirements: SOLAS, USCG, MED, and IMO LSA approved
Technical specifications
| Product type |
Personal rescue strobe light with water activation |
| Item number |
3971.3 |
| Model |
Firefly PRO Waterbug |
| Packaging |
Retail packaging |
| Operation |
Automatic water activation and manual switch |
| Modes |
Armed, strobe, SOS strobe, and steady-on |
| Light intensity |
41 candela per flash |
| Beam |
360 degrees, wide-beam LEDs |
| Visibility |
Over 4.8 kilometers |
| Flash frequency |
Approx. 60 per minute |
| Operating time (flashing) |
More than 56 hours |
| Operating time (steady) |
28 hours |
| Light color |
Cool white, without yellow tint |
| Batteries |
Two AA, not included, lithium recommended |
| Waterproof |
Factory-tested to approx. 10 meters |
| Dimensions |
Approx. 11.7 x 5.7 x 2.8 cm |
| Weight |
Approx. 68 grams without batteries |
| Housing |
Military specification |
| Approvals |
SOLAS, USCG, MED, IMO LSA, and CE |
| Brand |
ACR |
Extra features
| Armed mode |
In this mode, the light waits and turns on automatically as soon as it hits water |
| Difference from 3970.3 |
The standard Firefly PRO has no water activation and only turns on manually |
| Attachment |
Two attachment loops and an included Velcro strap |
| Replacing batteries |
Replace lithium batteries every five years or before the expiration date |
| Note after a wet day |
If the light is in armed mode and gets wet on deck, it will turn on |
Frequently asked questions
How long does a Firefly PRO stay lit?
The light flashes continuously for more than 56 hours on AA lithium batteries and lasts 28 hours in steady-on mode. That is over 48 hours longer than required by SOLAS and the USCG.
Which batteries do I need?
Two AA batteries, which are not included. Lithium is recommended as they last longer and perform better in cold conditions. Replace lithium batteries every five years or before the expiration date on the battery.
Why cool white light?
The light is intentionally cool white, without a yellow tint. This light carries further over water, making you visible from a greater distance than with a lamp that has a yellow hue.
What is the difference from the standard Firefly PRO?
The Waterbug features water activation and turns on automatically as soon as it is submerged. The standard Firefly PRO (item number 3970.3) only turns on if you switch it on yourself. For a life jacket, the Waterbug is usually the better choice.
Does the light turn on in rain or spray?
The light activates upon submersion. If it is in armed mode and gets very wet on deck, it can turn on. Therefore, turn the light off when not in use and set it to armed only once you attach it to your life jacket.
Downloads and official information
