The super-strong rare-earth magnets are great for DIY projects and perfect for sticking notes on fridge doors. The magnets are electrically conductive so they can be used to extend protected lithium batteries with recessed contact points (like protected 18650 CR123A etc). They are super strong rare-earth magnets - once they get stuck with each other they are hard to break apart. - Electrically conductive - Can also be used to extend protected lithium batteries with recessed contact points (like protected 18650 CR123A 14500 etc). - Super strong -- once they get stuck to each other it's takes a lot to pull them apart - Perfect for sticking notes on fridge doors - Great for DIY projects