Nicely designed badge.
Obverse
鮮満 - Sen-Man (as Korea and Manchuria were collectively known)
視察記念 - Visit Commemorative
reverse
昭和十二年五月 - May 1937
主催 - Organized [by]
ジャパン・ツーリスト・ビューロー - Japan Tourist Bureau
日本旅行協會 - Japan Travel Agency
See also related badges...
See also https://asiamedals.info/threads/tokyo-nichi-nichi-shimbun-sen-man-shi-tourist-group-badge.23869/
Obverse
満州國視察大毎旅行會 - Manchukuo Sightseeing Osaka Mainichi Shimbun Travel Association
In the center emblem of Mainichi Shimbun newspaper https://en.wikipedia.org/wiki/Mainichi_Shimbun