Hoya 49mm UV / IR Infrared R72 HMC Filter

HOYA UV-IR filters. These are specialized filters that cut BOTH UV rays below 390nm and IR rays above 700nm. This is important because the visible spectrum is between 400-700nm. Basically UV rays and IR rays both can diminish image clarity and sharpness. But by blocking them both before they get to the image sensor there is a noticeable increase in image quality.