Pros: It fits perfectly to replace the bulb of my mag lite with a P7 SSC led directly driving with 3 Ni-Mh D cell.
I added another empty cell (as a short circuit) to reach the full battery capacity .
The only mods i added are:
i turned on a lathe the head of the reflector to let it go inside the head of the mag lite (about less than 1mm).
i turned upside down the battery to avoid short circuit.
REMEMBER that the P7 SSC led have POSITIVE (in the bottom) in contact with the reflector and the case of the mag lite is NEGATIVE. Just turning upside down the battery cell, everything works well.

Cons: none
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Other Thoughts:

Bottomline: Very good reflector, clear, has a medium spot that is useful in short distance to about 150 mt.

Pros: Focuses P7 to give awesome throw, large concentrated hotspot, and giant bright spill.
Conducts heat from emitter to pill to reflector to head very well.
Unmodified, drops right into WF-500 head.
Modified, makes Mag C/D head into same torch as sku 14412.
Reflector is direct replacement for several P7 torches with same diameter reflector.

Cons: Pill doesn't appear to be pure copper (probably is brass), which made it more difficult to cut (see other thoughts).

Other Thoughts: To fit this into a Mag C, I had to cut off the bottom 1/2" of the pill with a pipe cutter, otherwise the head would not screw down past the gasket on the body. Reduce the height of the Mag head threads with a file, then dremel the inside edge of the head to a 45 degree angle. Dremel off a bit of the threading on the outside edge of the reflector and file down the top a little and this will sit nicely inside the Mag head with a single glass lens with the bezel fully tightened.
Electrically isolate the P7 slug (which is LED+) from the pill with Arctic Adhesive to avoid short/explosion.
Dremel off the top part of the Mag C body and then file down to the top thread and the body will then make direct thermal and electrical contact with the cut bottom of the pill.
I've done all the above and then made direct electrical connection between LED- and pill and installed long spring for contact between LED+ lead and contact in Mag bulb socket.
Direct driving a P7 D-bin in my Mag 3C with 3x AccuPower LSD NiMH cells ROCKS! (Beats my 2*18650 P7 for power and runtime and has safe chemistry.)

Bottomline: Inexpensive part that can be used to make an absolutely awesome torch.

Pros: This reflector offers an extreamly tight beam. Better than a 8deg MR16 or 6deg 10w HID when used with a P7 LED.
The copper base can be unscrewed and you can mount a bare emitter to it.
The base and reflector then act as a heatsink though I think you will also need more heat sinking.

Cons: To get it to mount in a mag head flush you need to grind/machine down the lip. It took me 30 minutes with a dremel and sandpaper.
Be carefull that it does not get too hot as it seems to be coated and this may blemmish.
This then allowed me to use 2 x 1.8mm glass lenes.
Short range it does give a slight donut effect but its not a problem

Other Thoughts:

Bottomline: Very very good choice for a mag dive light conversion.
Im happy.