I bought my computerized machine and just scanned the book.I had been sewing almost daily for about 2 months wearing two of those magnetic braclets, one on each wrist. I needed to find out what one of the feet could do. I decided to completly read the manual, It said no magnetics near machine.oops. My machine is now 5 years old & I never had a problem. I've also used a magnetic seam guide a time or two.