The StreamLight TL-2 comes with a 1W HD Luxeon and a simple resistor
for current control. A wizard buck/boost circuit was installed in an "Ecan" with a custom
heat sink plug that mates to a modified Pelican M6 reflector which was used
in place of the stock reflector. The improvement provided by the Pelican reflector is
marginal and likely doesn't justify the added work and expense. In the photo below, the
light on the left houses the custom LED module and the light on the right is stock.
Below, the modified PM6 reflector and custom module is on the left with the stock,
again on the right. The Pelican reflector is deeper and the height of the custom module
was shortened accordingly. A different sink plug could be made to mate with the Ecan and
still conform to a reduced diameter at the LED for allowing a fit with the stock reflector.
I believe thermal relief was improved with this particular mod since the sink plug is
considerably more massive and the mounting surface for the LED has a much larger radial
surface for thermal conduction. The PM6 reflector is also in compression against the face
of the sink slug (fixed focus) as opposed to a coil spring which separates the stock module
from its reflector.
Although the buck/boost circuit used will provide constant current of 450 mA to the LED
over a wide range of voltages (2.5 - 9 volts) it is less efficient than a simple buck circuit
would have been. Even allowing for this inefficiency, the custom unit draws 350 mA of
current at 5.8 volts whereas the stock unit draws 516 mA. A relative lux reading from about
a meter showed the stock unit putting out 940 lux with the custom one giving a reading of
1160 lux. The beams are very similar with the custom unit having a slightly larger diameter
hot spot than the stock unit. The differences are to slight to warrant photographs. Aside
from an increase in battery run time, slight increase in brightness and the stability of a
constant current supplied to the LED, this modification is hardly justified as is. Other
modifications based on the Ecan and using colored LED's or 5W LED's could be justified
depending on the merit of such changes.