Squares with a Different Line Direction in each half square

Image size:  5 3/4 x 5 7/8 inches each  (14.6 x 14.9 cm each)
Plate size:  7 1/8 x 7 1/4 inches each  (18.1 x 18.4 cm each)
Paper size:  14 1/2 x 14 1/2 inches each  (36.8 x 36.8 cm each)
Edition of 25, plus 7 AP, 7 PP, 3 known TPs
Signed lower right and numbered lower left on each sheet
(Inventory #22168)
Krakow 1971.03