It was originally used by government officials equal or superior to Sakan to submit a report personally to their superiors, and it was created in a format in which a Chinese character "cho" (牒) was written at the beginning, the main text was concluded with a phrase "tsutsushimite chosu," (謹牒) the date and Isho (rank and name in a row) were written in the last line and a character "cho" (牒) was inserted below Isho.
本来は、主典以上の官人個人が諸司に上申する際に用いられたもので、その様式は書出に牒の字を記してから本文を記して、謹牒（つつしみてちょうす）の書止で締めくくり、最後の行に年月日と位署（官職・位階・氏名）を書いて位署の下に「牒」の一文字を入れたものである。