Bisun - making a range of LED lighting systems for cavers.
Complete twin-beam caving lights and drop-in upgrades.
Bright spot beams for Duos. Dive and Photo lighting.

Bisun Flexitwin V5

Seriously powerful twin-beam LED units for Duo headlamps.

The V5, with its 'variblend' operation modes, gives simple independent control of total power and beam blend, which is arguably the best way of controlling a twin-beam light with a two-way switch, being easy to learn and simple to use, but giving great control over the output.
There is also instant 'reversible' access from any output setting to a full power spot beam with just a flick of the switch.

High maximum output of 500 lumens.

Constructed on a one-piece copper heatsink plate.

Intelligent memory to make operation simpler and easier.
The V5 turns on at the levels it was at when last turned off, even after battery changes. In the case of power disconnection while running, the unit carries on where it was when power is reconnected.

Full but discreet thermal limiting at all power levels.

Selectable power ranges to suit various output/runtime requirements.

Punchy spot beam and gently centre-biased flood LED to make the most of your power.

Redundant circuitry for maximum peace of mind.

Tolerant of poor switch condition - the 'variblend' modes only use the switch to change levels, not to power the light.

The Flexitwin V5 operation instructions are (here).

The Flexitwin is quick and easy to fit, and works in all Duos.
In some old (pre 2004) Duos where the battery_to_headset wiring was of random polarity, the cells may have to be flipped in the battery holder.