All SewTites are made with high-quality rare-earth magnets. The Midi Mix contains:

• Original - 1.78 x .5 in (45 x 13 mm) with three medium-strength magnets on back + matching metal plate
• Mini - 1.25" x .5" (32 x 12 mm) with two medium-strength magnets on back + matching metal plate
• Dot - .67" (17mm) diameter with one medium-strong magnet on back + matching metal plate