It's a horse racing simulator. Why these were popular in Japan, we honestly have no idea, but maybe you want to try to find out for yourself. In that case, pick this up, and you can breed and race horses on your Super Famicom to your heart's delight!
NOTE: All photos depict good condition items only; actual product may vary.
Used Winning Post (poor box, poor instructions)
Used Winning Post (poor label, poor box, poor instructions)