Knox® System Security Knox has taken system security to the next level. In addition to vault-like key boxes that exceed the requirements of three UL listings, the Knox® Master Key is protected by two optional systems. KeySecure® 3 KeySecure® 3 is a keypad-controlled unit with audit trail that retains the Knox Master Key in emergency vehicles. Fire Department personnel simply enter their authorized pin code and a Knox Master Key is released for service. The master key is locked in a visible position providing immediate accountability. An illuminated keypad clearly displays the buttons for pin code entry day or night. There is also an LED indicator that displays red for an unsecured key or green for secured. Once secured, the key is locked in place until the next pin code is entered to authorize key release. Next Generation Sentralok® Sentralok® A Sentralok® A is an enhanced and contemporary analog replacement of Sentralok I. Sentralok® A enables the Knox master key to be released by dispatch through a two-way radio signal. This state-of-the-art product includes some new and important added features like full audit trail, infrared communications with PDAs or Laptops, four digit scanning LED informational display and keypad pin code access. Sentralok A communication can be DTMF or the much faster MSK (600 or 1200 BAUD). The Sentralok Encoder is replaced with a Knox PC-based Windows application software that generates the proper release code frequency via a standard modem (MSK) or sound card (DTMF). For more information ...