Laser Products Surefire 6P Classic 

This product dates back to the late 1980s and early 1990s, and it was a well-known product from Surefire (Laser Products). The key feature of this light is that it uses camera batteries, the 3V CR123A lithium primary batteries, with two batteries providing 6V (actual operating voltage is around 5V), which is also the origin of the product's name. Compared to the heavy and dim Maglite, Surefire's marketing emphasized that this compact flashlight was much brighter than a 4D-cell flashlight.

The price at the time was extremely high, even the batteries were very expensive. However, due to its small size and very bright output, it gained a foothold in the US law enforcement and military markets, which helped establish the Surefire brand. In the late 1980s, this product was introduced to the local Hong Kong, reportedly selling for over $600 HKD, with the batteries costing over $20 HKD each. When Surefire discontinued all their incandescent flashlights in 2015, the prices were still similar.

This flashlight uses a P60 6V xenon lamp with 65 lumens of output. The lamp and reflector are integrated and cannot be disassembled, making the part quite expensive. Under normal use, the lamp life is around 20 hours. Using the P60 lamp requires 40 CR123A batteries for 20 hours of runtime. Nowadays, there are Chinese-made replacement xenon lamps (commonly called 26.5mm lamp assembly) that are only a tenth of the price, and there are also many options to use with inexpensive rechargeable batteries. For safety reasons, I personally only use 3.2V lithium iron phosphate (lifepo4) batteries, paired with 7.4V or 9V lamps, which provide brightness close to the P60 but with a warmer color tone.

The first generation 6P has a round body, but there are actually several versions with different lengths, knurling depths, and shapes. It's important to note that the lens is made of plastic. If you accidentally leave the light on and place it lens-down on a surface, the plastic lens can melt quite quickly. The main purpose of the plastic lens is that no matter how the flashlight is dropped or impacted, the lens will not shatter, unlike glass lenses. The plastic lens is not inferior or outdated - in fact, there are practical considerations for its use, especially in military applications. I actually believe that Surefire's later transition to all-glass lenses was a step backwards.

Most Surefire lights use a modular design, where all the accessories within a product line can be interchanged, regardless of age. This means that if any part gets damaged, it's easy to find a replacement or customize the flashlight to your desired configuration.