The Mizuno MP-5 iron set is the ultimate blend of a classic muscle back and a players cavity design. The new Channel Back design is a way of distributing the weight around the club head to allow for increased forgiveness while still maintaining feel and look of a traditional muscle back. The MP-5 is grain flow forged from a single billet of 1025E Pure Select Mild Carbon steel for a soft, solid and consistent feel. Mizuno uses its scientific Harmonic Impact Technology (H.I.T.) to fine tune the sound and feel of every iron.