Double rollers spinning anti-static cloths in opposite directions cleans both sides of carded and roll film.  The eight anti-static cloths on each spindle will clean up to 3,000 carded negatives.  The cloths can be reversed 4 times allowing up to 12,000 carded negatives to be cleaned before replacement is required.  Anti-Static cloths are easily replaced by simply sliding the cloth out of the slot, folding a new cloth over the holding pin and re-inserting.  Film cleaner can be operated in either continuous mode or intermittently by using the foot switch.  Will work either upright or on its side.  Replacement cloths are available from Saint Charles Research.