The tubular lock, in the form of the regular 7 pin version* has been around fur many years: having been invented in the mid-30's. It was so named, "tubular", because of its key being a tube with the tumbler cuts cut around it. The tumblers in the lock mechanism are parallel to the axis and located radially around it. Its high security is basically because of its relocking every 45 degrees of rotation. In a cam type lock, you would have to pick it 4 times to effect 180 degrees of rotation to open the lock. This feature becomes even a greater security factor in the stud type lock that must be rotated as many as 8 to 12 times to open. This type of tubular lock has found great usage on vending machines and coin changers...