Kalea Premier irons are powered by Cap Back Design, which provides?stability?within the topline and upper perimeter of the face, working in conjunction with the Speed Pocket to?optimize?face flexibility,?ball speed and distance. The Cap Back Design also helps minimize unwanted vibrations in the head to deliver a soft and solid feel. Head shaping has been designed uniquely for Kalea Premier to create SGI forgiveness in a sleeker and more elegant overall profile.