These hollow iron-wood designs put a major emphasis on ease of launch, playability, and correcting miss-hits and slices to go straighter for the ultimate in ease of use.The improved hollow-body design of the Hot Launch E523 Iron features the game-changing Houdini Sole in conjunction with a super-shallow face, slice-fighting offset designs, and heel weighting for an added draw bias.HOUDINI SOLE TECHNOLOGYThe Houdini Sole is a raised steel mass area at the rear of the club head, as well as a curved leading edge under the face. The patented Houdini Sole reduces the amount of sole area to reduce drag and turf interaction by 35% and is instrumental in significantly altering the CG placement of the E523 Iron, making it one of the highest-launching and easiest-to-hit irons ever produced.HOLLOW BODY PERIMETER WEIGHTING- Hollow-body perimeter weighting produces distance properties of a metalwood in an iron-like design. Hollow-body perimeter weighting produces maximum ball speed off an iron. The hollow-body design makes for an extremely low and back CG, helping to create a very forgiving and powerful face.SHALLOW FACE/OFFSET DESIGNThe super-shallow face coupled with an offset design is designed for extreme playability and high-flying launch characteristics. The offset design acts as built-in slice-fighting technology, squaring the clubhead at impact to produce anti-slice ball flights. The extremely shallow face produces higher launch angles and extreme ease of launch with extreme forgiveness.CONCAVE BODY DESIGNA new concave design added to the E523 Iron creates our best looking hollow-body iron-wood to date. The concave treatment to the shape of the E523 Iron creates a smaller topline, and a less visible backend for a more compact look at the address, while still providing the forgiveness and ease of launch that our iron-woods have become famous for.