In a mixing bowl, combine sweetened condensed milk, powdered sugar, and graham cracker crumbs until well mixed.

Shape the mixture into 1-inch balls and place on a baking sheet lined with parchment paper.

Melt the chocolate chips and butter together in a microwave-safe bowl, stirring until smooth.

Using a fork, dip each ball into the melted chocolate, ensuring it is fully coated. Place back on parchment-lined sheet.

Refrigerate the truffles for at least 2 hours or until set.