"I will start out by saying that this new track pack is much better than the old pack (7499) in terms of included pieces. It includes straights, flex track, AND curves, making it an all-in-one option for extra track. However, the best case scenario for older fans like me would be the option to buy all types of track separately. But for parents buying extra track for their kids, this is perfect. It gives you just the right amount of each track type, making a good addition to any train set.
Note: Works with 4.5v, RC, Power Functions, and Powered Up trains. (NOT for 12v or 9v)"