Mexicans can enter the United States for 3 days at a time, but they cannot go farther than 50 kilometers(60 miles) into the country. Therefore the Border Patrol has set up checkpoints along roads that lead from the border into Texas. At the checkpoints there are Border Patrol Officers and drug sniffing dogs. As we travel around the mission, we have to pass through these checkpoints. They always ask if we are United States citizens and sometimes they look in the mission trasfer van that we drive. I have an army ammunition box that I carry my tools in. This caused some questions from one of the Border Patrolman on one occasion.