I wanted something I could take along to the gym to vary my workouts, sometimes when left to my own devises I just repeat the same old stuff! I also found alot of books assume you don't have access to any equipment so I like the fact this does use stuff like body balls/resistance bands etc. There is also plenty you can do with just your body / some small weights though.
It's handy that I can just grab the few cards I want and take them along. (I do use them at home as well.)
There are some training techniques cards, 9 example circuit workouts and a total of 78 numbered exercises (it says 50 on the box but 78 includes the variations of an exercise).
Example Exercises: Back Kick with Shoulder Press (weights) Squat Thrust (using a medicine ball) Dropsy (a stepping style exercise) Dumbbell Fly on Body Ball with Crunch Boat Pose Crab Walk There's plenty of squats, jumps, crunches etc with variations too.
I find the cards easy to follow, I generally read the whole thing through before I do one for the first time then use it as a reference and to check my technique.
It's just what I needed to keep challenging myself and not getting stuck in a rut!