The "Floating Hook" on end of a tape measure

That little "wiggle" isn't a manufacturing defect—it's a precision feature called a floating hook. It moves to ensure you get a "true zero" reading whether you are measuring from the inside or the outside of an object.

The distance the hook slides is exactly equal to the thickness of the metal hook itself (usually 1/16 of an inch or 1mm).

How It Works:
Outside Measurements: When you hook the tape over the edge of a board, the hook pulls out. This adds the thickness of the hook to the measurement, starting the "0" mark at the very edge of the board.
Inside Measurements: When you butt the tape against a wall or inside a drawer, the hook pushes in. This "hides" the thickness of the hook so the measurement starts exactly from the surface you're pushing against.



I thought those that weren't aware would benefit from this riveting knowledge. Thanks.