[Review] Lumintop D2 || 1 x 21700 / 18650, OSRAM GW.PUSRA1 PM || Output, Beamshots and Thermal Regulation Results

The flashlight was sent to me by FlashlightBrand for review.
Here's the product's link for more info: Lumintop D2
And a link to FlashlightBrand's Lumintop collection

The Lumintop D2 comes in a typical cardboard box.

The light is seated into some laser cut foam to protect it during shipping.

The following accessories are included:

  • Adjustable wrist lanyard
  • Samsung 35E 18650 cell
  • USB-A to USB type-c charging cable
  • Split ring
  • User manual

The D2 is a compact thrower flashlight.
It comes in a black anodization and is e-switch operated.

The e-switch is mounted on the lower part of the head.
An indicator LED is in place and will stay lit once the flashlight is turned off and act as a beacon.
Additionally, the indicator will flash during charging to signify the charge's state.

Opposite to the e-switch you can find the charging interface, which uses a normal type-c port.
The port is covered via a rubber flap to keep moisture and dust out.
While charging I recorded a maximum current of 2A.

The head and tail of the light comes with a subtle, square texture, while the head integrates some headsinking grooves.

At the front of the head we can see a smooth bezel that provides a bit of a lip to protect the AR coated lens.

The head houses a smooth reflector along with an OSRAM GW.PUSRA1 PM emitter.

The head can be easily taken apart.
As we can see, the emitter sits on a copper star. The star is held from rotating via a screw, while plenty of thermal paste seems to be in place.

A thick steel spring is used as the positive terminal of the light.
The driver seems to be friction-fit / glued into place.

A long copper spring is used on the tail side.
Most probably the choice for a longer than usual spring is made to allow the flashlight to accommodate both 18650 and 21700 cells.

Both the tail and head threads of the body are anodized and arrived adequately lubricated.

The tail of the light is flat, which allows it to tailstand.
A little hole is also in place to allow the installation of a split-ring or lanyard.

As said previously, the Lumintop D2 arrived with a Samsung 35E 3500mAh cell.
Additionally, a 21700 to 18650 adapter is also included.

The cell is a flat topped one, but the flashlight can work both with flat tops and button tops cells.

Out of curiosity, I went ahead and measured the resistance of the include type-c cable @ 1A.
It turns out that the cable is very decent, as it reported 0.06Ω of resistance.

User Interface

The Lumintop D2 comes with a pretty straightforward UI.
Here's the actions supported:

Turn on: Single press
Turn off: Long press (1s)
Mode cycle: Single press (Low > Medium > High > Low > ...)
Turbo: Double press
Strobe: Long press (2s) while off.
SOS: Single press from Strobe.
Lock / Unlock: Long press (5s) while off.

Low voltage warning and protection is in place. Mode memory is also on.
My only gripe about the UI is that is concentrates a lot of its functionalities around the Long press while off (Lock/Unlock, Strobe).
It would have been way better if strobe could be accessed differently (maybe via Triple press). This way the lockout wouldn't require the user to also go through the Strobe.


Here's my output measurements along with the current draw for each output level.

As we can, Lumintop has done an excellent and honest job at providing their flashlight specifications, since my measurements are very close to the official values.
The D2 pushes 980 lumen while drawing 2.90A at Turbo.

Thermal Regulation

Here's a thermal regulation graph during a 20 minute run.

What we can see in the graph:

  • Turbo is sustained for 13 minutes.
  • Once turbo has saturated the flashlight's body with heat, it will step down to High.
  • High and Medium are fully sustainable for the whole span of the test.
  • All modes show signs of constant current regulation (same current no matter the input voltage), which is always a good thing.


And finally, here's some outdoor beamshots.

Wow, it’s impressive to see a Lumintop light have such good regulation! How long did High and Medium last? As the test only goes up to 20 minutes.

Yup, regulation is looking good!
Give me a day or two and I’ll try to run some more tests for High and Medium and will report back with the results.