Japanese incense (speaking in general terms) is refined, pure, light smoke and rich in natural ingredients such as sandalwood. They don't usually have the thin wooden stick centre that is often found in Indian and other incense sticks. They are normally pure incense right the way through the stick. They are often designed with meditation in mind. Due to the high quality manufacturing processes the incense goes through they can be a little bit more expensive than other incense on the market.
To find out more read:The History of Japanese Incense