Ages: 7+ ages， both for kids and adults.Operating temperature: 80 degree Celsius/176 FahrenheitMagnets Type: Neodymium.Disc Size: diameter 100pcs 5mm x thickness 1mm. 100pcs 6mm x thickness 1mm. 50pcs 5mm x thickness 2mm 50pcs 5mm x thickness 3mm.. 50pcs 8mm x thickness 1mm. 50pcs 8mm x thickness 1.5mm. 50pcs 10mm x thickness 1mm.Rating: N50. Package Included: 100PCS/50PCS Magnets.Features:1. Super strong Rare-Earth magnets， once they get stuck with each other， they are hard to break apart.2. Can also be used to extend protected lithium batteries with recessed contact points.3. Electrically conductive (making them suitable to extend recessed batteries).4. Neodymium magnets are usually coated Nickel-Copper-Nickel plating to prevent the iron from rusting.5. Perfect for sticking notes on fridge doors. Great for do-it-yourself projects. http://contestimg.wish.com/api/image/rating?name=7d7d7a927ae011e6a922065f903a9ac5.jpg&w=1000&h=1000&m=0&t=0