With my new photography hobby, I wanted to purchase something to keep my camera lenses clean. I didn't want to spend a lot of money, and I was looking for something that would be easy to keep in my camera bag to use while I was out on a photo shoot.
The Hakuba Lens Pen fits the bill in both of those categories- it is about the same length as a pen you would use for writing, but a little bit thicker. Each end of the lens pen is functional- one end has a cap that comes off; the end of the pen is shaped in an almost flat disc, and is covered in a microfiber cloth. You can use this function to rub onto a glass lens surface to "erase" smudges. The other side of the pen has a retractable brush mechanism, which can be used to brush the lens off, removing dust or small particles.
I think that the Hakuba lens pen is great for portability- I have even carried it in my pocket with no problems, but I feel that it is lacking a little bit in the fact that it doesn't have a blower mechanism. You have to be so careful anytime you are cleaning a glass lens, so you don't scratch the surface. I have found that anytime I have dust or dirt on my lens, the best way to remove it is to blow it off the lens surface, and then use a brush afterwards. You definitely would not want to use the microfiber end if there are visible pieces of dirt on the lens, or you will grind it into the surface of the lens, scratching the lens. On the other hand, if you use the brush feature for something like a fingerprint, it just smears it around, not really cleaning it.
So, all in all, I think this was just an "ok" purchase. While it has come in handy a few times, I think a blower would be something that will be used more often.