What is resin impregnated honeycomb?

This is a manufacturing method used for boards or shell components that must be very lightweight, but also extremely strong. You've seen this concept in cardboard boxes - the latticework provides rigidity.

In typical cardboard, this latticework runs parallel to the outer shells. In the case of resin impregnated honeycomb, the lattice is perpendicular to the outer shells - creating a series of honeycomb shaped boxes for extreme rigidity.