Michael: (voiceover) When you need to get into a building in a hurry you can always count on a fire exit. Every building has them. It's just about knowing how to use them. The right shape charge, will put a big enough dent in a steel door to disengage the lock which can turn a fire exit into a convenient and unexpected entrance. A coil of det cord attached to a rubber mat will give you the explosion you need and allow you to point it wherever you need it to go. SWAT teams call it a hockey puck.