Add on yellow filter that fits over the objective lens cover of SL390/360 Mediworks slit lamps. 
 
The filter can be used for early detection of micropunctate corneal staining caused by contact lens/solution interaction, early detection of the correlation between patient symptoms and signs of dry eye syndrome, and better visualization of RGP fluorescein patterns. The filter is encased in a sturdy plastic frame and is recessed to reduce filter damage and scratches."