uptodatetools Angle Finder Magnetic Base 4-1/8" 4 inch Magnetic Inclinometer Level (15 cm) Magnetic Inclinometer Level  (15 cm)

The indicator on this angle finder is accurate to 0.5 degrees, so there’s no need to use a protractor or manual angle finder again! The angle finder magnetically attaches to metal squares for easier reading and can be mounted to nonmetallic squares with self-threading screws (sold separately). Check angles from 0 to 90 degrees--this angle finder comes with a conversion chart for determining pitch per inch and foot.