A collage of three photographs showing the different types of NAC Core and NAC Shell. The first photograph on the left shows a close-up of a piece of paper with a green circle in the center. The circle is labeled "afar" and is surrounded by a thin black line. The paper appears to be slightly wrinkled and has a brownish-brown color. The background of the photographs is white and there is a red line on the right side of the image. In the middle photograph there are two circles one labeled "cherry" and the other labeled "NAC Shell". The circles are overlapping each other and the red line is pointing towards the center of the circle. The green circle is slightly larger than the black circle and is slightly smaller than the two circles. The red line appears to have a small amount of dirt or grime on it indicating that the paper has been exposed to the elements for some time.

• Photograph

• Outreach and Education