A more thorough explanation:

Definition: A duplicate will is a type of will that is executed in duplicate originals by a testator who retains one copy and gives the second copy to another person. The rules applicable to wills apply to both wills, and upon application for probate, both copies must be tendered into the registry of the probate court.

Example: John creates a duplicate will and keeps one copy with himself and gives the other copy to his lawyer. Upon John's death, both copies of the will are submitted to the probate court for validation.

Explanation: A duplicate will is created to ensure that the testator's wishes are carried out as intended. By keeping a copy of the will with another person, the testator can ensure that the will is not lost or destroyed. Both copies of the will must be submitted to the probate court to ensure that the will is valid and that the testator's wishes are carried out.