Sensor cleaner permits view at the same time

LENSPEN SensorKlear Loupe system for cleaning DSLR sensors, lets you see what you are cleaning while you clean. Product simplifies and speeds sensor cleaning. Product is easy to use; just remove the camera lens, place the Loupe on the aperture ring, turn on the light and inspect the sensor. If it’s clean, there’s nothing left to do but put the lens back on. If the sensor is not clean use the Hurricane Blower to remove the dry dust. Inspect the sensor again.

http://www.lenspen.com