Muscleback blade golf clubs, like the Taylormade P7MB, are irons with a blade-like design in which the weight is evenly distributed behind the sweet spot. These irons are targeted towards highly skilled players who consistently hit the middle of the face. The Taylormade P7MB is a muscleback blade iron that offers a beautiful look and feel. However, it is less forgiving compared to other Taylormade iron models.