🛡️ DIY Faraday Cage with an Ammo Box 📱 Ever thought about protecting your small electronic devices from electromagnetic interference? Try an ammo box as a makeshift Faraday cage — But how do you know if it works? Place your phone inside the ammo box. Seal it up. Try calling your phone. If it doesn’t ring, it’s not getting a signal - a good sign that your box is blocking electromagnetic fields. The ammo box I’m using is steel and has a rubber gasket, ensuring a tight seal against water and dust

DAY 3 of 10: Get 50% OFF all ammo boxes! Valid Wednesday, 9/25 ONLY. In-store only. Get your coupon in the #HarborFreight mobile app and check back daily through 10/2 for new deals. | Harbor Freight