If you get MT4.1 the harder of the 2 papers, there is a mixture of questions, on joints, pivots, levers, sliders, bell cranks, tree felling, rivets, pipes, pulleys, rack and gears, cams, flag poles, tyres, wheels, circuits and liquids from what I remember, plus other stuff. MT4.2 is the far, far easier one and its mostly questions on cogs [if cog A turns clockwise what does cog E turn], pulleys and gravity, but it seems to be very rarely used now, though it used to be used all the time going back 5+ years. However you dont need mechanical experience to pass either of these papers. I didnt have any the first time round, and have sat MT4.1 three times and MT4.2 once and passed them every time. What really helps is that you dont run out of time and get to the end of the test. If you run out of time and leave about 10 questions blank at the end, thats not going to help at all. There is no book that helps with MT4.1. The Barrons book is just about the best of a bad bunch. It will help with maybe 2 or 3 questions that are in MT4.1, out of the 36.