From memory it was 350 questions of dullness that sucked the life out of you however, do not try and answer the questions they way you think they want to answer them. I did this on the initial selection tests at the same time but you will be presented with the same question worded throughout the 350 questions about 8 different ways therefore answer them truthfully.
Some of the oddballs I have worked with in NATS over the years makes me wonder what they are really looking for. Good luck