It's Not Just The Size Of The Cavity\nFor those not on tour, TaylorMade's titanium–face, stainless–steel frame Burner XD irons feature an inverted–cone design within the cavity to produce consistently higher ball speed across a wide area of the clubface. The perimeter weighting is similar to that of an iron with a conventional sole because of the use of multiple materials.\n\n $900\n\n taylormadegolf.com\nFor the better player: Wilson Staff's new Pi7 irons, which were built with input from Open champion Padraig Harrington. The head has a small profile and features a cavity lined with a special rubberized paint, originally developed as an undercoating for steel bridges.\n\n $600\n\n wilsonstaff.com\nSimilarly, Nike's fourth generation of its slingback cavity, the Slingshot 4D, combines variable sole width (wider soles on the long irons get progressively narrower) with a variable position of the rear bar (higher in the cavity on the short irons and lower in the long irons).\n\n $800\n\n nikegolf.com\nThe key to practice is minimizing harm. In this case, we're talking more than just keeping doubles and triples off the scorecard. Weighing 13.5 grams (about one–fourth the weight of a regulation ball), the Point 3 practice ball ($10 for 10, almostgolf.com) is made from the same material used in synthetic wine corks. Windows, cars, pets and small children will be safe if you decide to hone your move in the back yard. It flies 30 percent of a normal ball, and the trajectory is good enough that the University of Southern California recently held an 18–hole tournament across McCarthy Quad, an acre–size grassy area on campus.\n\n Another product showing its softer side is The Golf Mat ($199, thegolfmat.net), an artificial–turf mat whose bottom layer arches subtly like a bridge. The arch bows down at impact to replicate the feel of swinging down and through when making a divot and to reduce shock to your joints.