The KLx are Konversion LED Bezels.
Check out this photo gallery for the KL2 & KL3:
http://www.pk-engineering.com/kevin3.html
There are four products here:
KL
1
Fits on the E1, E1e, E2 & E2e.
A single Luxeon - digitally regulated.
The output is practically the same regardless of whether you power it with one or two SF123As. The runtime of the KL1 powered by two SF123As is longer.
KL
2
Fits on the M3.
19 LEDs - [edited by Al] I assume digitally regulated - exactly how I am not sure... The output is constant brightness for a very long time as far as I can tell.
KL
3
Fits on standard body two SF123A and three SF123A bodies such as the C2 & C3.
A single Luxeon - digitally regulated.
The output is practically the same regardless of whether you power it with one or two SF123As. The runtime of the KL1 powered by two SF123As is longer.
The
A2:
The A2 is a Digital Fusion of a Regulated incandescent bulb and three 5mm LEDs within the same reflector, activated by a two-stage pressure switch.
The A2 bulb is NOT the MN03. The output will be roughly the same Lumen output but the colour temperature is far whiter then any other bulb. Because it is digitally regulated, the bulb specification can be matched to the supply allowing the bulb to be more robust, have a longer life, and output a whiter beam.
Here is a photo of the A2 will a bunch of other SureFires:
I hope this helps?
Al