I assume you found the naturalization date from Acestry.com.

The important designation for the court is COUNTY COURT, Kings County. If one continues reading Ancestry's additional information, one will find . . .

For copies of the original file for naturalizations performed in other New York City courts, write to:

New York County Clerk's Office
Division of Old Records
60 Centre Street, Room 161
New York, NY 10007

Phone: 646-386-5395