THE HEART-SHAPED MAGNETIC PLASTIC CLIP IS MADE OF PS PLASTIC AND N35 MAGNETS. SMALL ROUND MAGNETS ARE ON THE BACK OF THE CLIP. IT CLIPS ONTO WHITEBOARDS, MAPS, FILING CABINETS, REFRIGERATORS AND ALL METAL SURFACES. COMPLIES WITH CPSIA. 2.76" L X 2.76" W X 1.26" H