7M views · 35K reactions | Foam-filled tires are made of regular rubber but replace the air inside with hardened liquid urethane. While they come with benefits like being impervious to flats, they can only be used on slow-moving vehicles. Still, companies are willing to pay thousands more for them than air-filled tires. | Insider Tech | Facebook

Using polyurethane foam, roads and pathways can be raised back up to level ground. 📽️: Instagram/ designexpertacademy | Interesting Engineering

115K views · 807 reactions | Here’s how firefighters use a few pieces of equipment to output massive amounts of firefighting foam.  ️ LEADER Group | Interesting Engineering | Facebook