 The metal clip was introduced in the post-World War II period, as a means to carry lunch boxes, change of clothes for P.E., etc.Around March 2014, American actress Zooey Deschanel took her picture with red "randoseru" on her back, and it is becoming the boom for young people to wear "randoseru".In recent years, in addition to the boom spread by the above-mentioned American actress, there are an increasing number of people outside Japan who know about "randoseru" through Japanese animation, manga, etc.