Naval Mobile Construction Battalion 133 (NMCB 133) is a United States Navy Construction Battalion, otherwise known as a Seabee Battalion, homeported at the Naval Construction Battalion Center (Gulfport, Mississippi) (aka: Naval Mobile Construction Battalion One Three Three or One Thirty Three). The unit was formed during WWII as the 133rd Naval Construction Battalion. It saw action and was decommissioned shortly after the war ended. The unit was reactivated as Mobile Construction Battalion 133 for the Vietnam War and remains an active unit today.