Form, Fit, and Function (FFF) Definition

Form, fit, and function (FFF or F3) define the parameters that set the characteristics of a part. Form - The shape, size, dimensions, mass, weight, and other visual parameters that uniquely distinguish a part. Fit - The ability of a part to physically interface with, connect to, or become an integral part of another part. Function - The action or actions that a part is designed to perform.
Form, fit, and function (FFF or F3) define the parameters that set the characteristics of a part. When you consider whether to introduce a new part number or create a new revision for an existing part number—it's important to consider and follow the form, fit, and function guidelines.

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