Get in the knife game with Viper Tec! Here at Viper Tec Knives you will find everything from Out The Front Automatic Knives to Automatic folders as well as regular knives, tactical axes, self defense supplies and anything else you might think of. OTF knives, Out the Front knives, or Switchblades. Whatever you prefer to call ‘em, we’ve got ‘em. While these knives are primarily used by and made for law enforcement, military personnel, and first responders, they make a great addition to any collection. Automatic knives, also known as switchblades, open automatically with the press of a button or pull of a lever. Designed primarily for military, police and EMT duty, the speed of an automatic knife is ideal for emergency situations.