Excellent, informative book
Bought for our four year old. She loves the pictures, lifting the flaps up, and asking us LOTS of questions about what she's looking at in the book, how that part of the body works and so on.
For her age, it's perfect as a conversation starter about how the body works and has led to lots of playing about with her elbows, knees, muscles etc Really good fun for all of us.
Would also buy for an older child who can read and wants to learn more about human bodies.