As the name implies the weight is concentrated in the rear corners giving deep blue extreme stability and an MOI of 6000 to help keep the weight rearward. The face is a fully milled 6061 blue anodized aluminium insert. This 3/4 " insert delivers a solid feel and a sound at impact , and at only a third of the weight of steel. The clean blue high MOI design gives the Deep Blue a swing weight of F2 that only feels like D7.