Surefire KT1 / KT2 Turbohead

The Surefire Turbohead series started with the T1 and T2 models, which had relatively thin bodies and used plastic lenses. However, they had a very simple and classic appearance.

Later on, the KT1 and KT2 replaced the earlier models. These had thicker aluminum bodies, were a bit heavier, and used glass lenses instead of plastic. 

The KT1 and KT2 are actually the same Turbohead, with no differences between the bodies. The only difference is the bulb that comes pre-installed - the KT1 comes with an N1 bulb for use with 2 CR123A batteries, while the KT2 comes with an N2 bulb for use with 3 CR123A batteries. The earlier bulbs had very tight, focused beams.

Over time, the N2 bulb could be replaced with the more common MN15 bulb, which allows the use of 2 rechargeable 3.7V lithium-ion batteries.

The KT1 and KT2 Turboheads have a very shallow reflector, which produces a wide, floody beam pattern, but with an extremely intense center spot. This combination of flood and throw was very well designed. This is in my opinion better than the later KT4 turboheads for the M4 and M6 lights. 

These Turboheads are compatible with the 6P series ("C-series") flashlights. They come in both black anodized (BK) and natural (HA) finishes. The modern styling allows them to be paired with a wide variety of flashlight bodies for a very sleek, stylish look.

However, they are now quite rare and expensive, if you can find them. There are also counterfeit versions from China, so caution is advised when purchasing.