Reflect on the past and learn about history all while piecing together this Smithsonian featuring a collage of war and military posters.andnbsp28 x 20. Precision fit, premium quality, glare free, virtually no puzzle dust, 1000 pc. Increases creativity. Provides personal and family fun. Develops visual-spatial reasoning. Enhances short-term memory. Improves concentration. Eases stress. Supports brain health. Improves work performance.