A printed circuit board that can be used to build a lightning detector.  The range is typically 50 miles.  The ferrite rod required is 100x10mm with about 60 turns of wire.  This is a bare printed circuit board only, no components or instructions are supplied.  Board is double sided with plated through holes, white silkscreen and green solder mask (both sides).  Dimensions 50x50x1.6mm.