Cobra RF Proto REV 33 Iron Set. Co-designed by Rickie Fowler and Cobra Golf, the Limited Edition RF Proto Irons are the result of 33 different revisions over the span of a year with one goal: To create the perfect iron. The rich copper finish was hand selected by Rickie as a finishing touch to make his irons truly one of a kind. (As per typical Fowler). Each RF Proto iron is carefully crafted using a two step process: forged and machined for 155 minutes using a computer-numeric-controlled (CNC) milling machine to ensure the most precise iron without any inconsistencies. Careful consideration was taken to ensure every aspect of the shape ranging from the topline thickness, to each edge radius suited Rickie’s eye. The design process began with Rickie hand shaping irons on a grinding wheel, and resulted in 33 different prototypes that were tested, and fine-tuned by Rickie himself. At first glance, one will notice the sharp edges and little to no offset that makes these irons strikingly different from anything played on Tour. Bear in mind they are seriously the smallest looking iron I have ever seen. The Pursuit of Perfection. Cobra’s slogan for the RF Proto is that they made 32 versions of a great iron, however; it took 33 tries to make the perfect iron. Limited Edition commemorative box included. This item is in the category “Sporting Goods\Golf\Golf Clubs & Equipment\Golf Clubs”. The seller is “golf-superstore” and is located in this country: US. This item can be shipped to United States.