Chief Pins Airman Navy Chief Warrant Officer Four Anthony Kalkbrenner pins Air Force Airman Marco Kalkbrenner, his oldest son, upon completion of technical training for security forces. Security Forces specialists go through extensive training in law enforcement and combat tactics to protect bases stateside and overseas. Courtesy photo SHARE: Download: Full Size (0.06 MB) Tags: Navy Credit: Courtesy photo VIRIN: 180425-O-ZZ999-004.JPG Photo Gallery