Stanley Fatmax Stud Finder 400 Manual May 2026

Mark the first red light location (this is one edge of the stud).

Continue sliding in the same direction. The red light will turn off (green returns), then red will reappear at the opposite edge.

Mark the second red location. The center of the stud is exactly midway between these two marks.

Pro Tip from the Manual: For the most accurate center marking, move the finder back and forth over the stud several times. The Stanley FatMax 400 is most precise when moving at 1 inch per second.

While this guide covers 99% of the Stanley FatMax Stud Finder 400 manual functions, you may want the official PDF for warranty registration or exact technical drawings. stanley fatmax stud finder 400 manual

If you lost your quick-start guide, follow these steps exactly: Mark the first red light location (this is

You don’t need to be a tech wizard to use this tool, but you do need to follow the calibration process correctly. Most "failed" readings happen because the user skipped this step. Pro Tip from the Manual: For the most

This section mimics the critical warnings in the original manual.

WARNING: The AC (Alternating Current) detection feature is for reference only. Environmental factors (drywall thickness, moisture, metal backing) can block the signal.