passing the physical exam as a Grade One conscript (former Japanese military)
Historical term from the pre-1945 Japanese military conscription system. Refers to being classified as physically fit for top-grade service.
Before the war, receiving a Grade One pass meant you were assigned to military service.
彼の祖父は若い頃に甲種合格だったと話していた。
His grandfather used to say that he had passed as Grade One in his youth.