Abstract: A golf club head includes a heel portion, a toe portion, a hosel, and a striking face. The striking face includes a plurality of scorelines each having an average depth no less than about 0.10 mm, a plurality of first micro-grooves each having an average depth no greater than about 0.010 mm, and a plurality of second micro-grooves overlaid on the first micro-grooves, each of the second micro-grooves having an average depth greater than the average depth of the first micro-grooves. Some embodiments can also have a plurality of textured surface treatment regions superimposed on the overlaid first and second micro-grooves so as to at least partially intersect the micro-grooves.

Abstract: A method of selecting a preferred golf shaft for a player who uses an existing golf shaft, according to one or more aspects of the present invention, may comprise gathering a plurality of empirical data sets, each data set corresponding to an individual golf shaft selected from a plurality of golf shafts; providing a plurality of specification codes, each associated with an individual empirical data set of the plurality of empirical data sets; from the plurality of specification codes, identifying a first specification code associated with the existing golf shaft; gathering feedback associated with the existing golf shaft from the player; and using the feedback to select, from the plurality of specification codes, a second specification code corresponding to the preferred golf shaft.

Abstract: A golf club head includes a heel portion, a toe portion, a hosel, and a striking face. The striking face includes a plurality of scorelines each having an average depth no less than about 0.10 mm, a plurality of first micro-grooves each having an average depth no greater than about 0.010 mm, and a plurality of second micro-grooves overlaid on the first micro-grooves, each of the second micro-grooves having an average depth greater than the average depth of the first micro-grooves. Some embodiments can also have a plurality of textured surface treatment regions superimposed on the overlaid first and second micro-grooves so as to at least partially intersect the micro-grooves.

Abstract: A method of selecting a preferred golf shaft for a player who uses an existing golf shaft, according to one or more aspects of the present invention, may comprise gathering a plurality of empirical data sets, each data set corresponding to an individual golf shaft selected from a plurality of golf shafts; providing a plurality of specification codes, each associated with an individual empirical data set of the plurality of empirical data sets; from the plurality of specification codes, identifying a first specification code associated with the existing golf shaft; gathering feedback associated with the existing golf shaft from the player; and using the feedback to select, from the plurality of specification codes, a second specification code corresponding to the preferred golf shaft.

Abstract: A system for fitting golf clubs to golfers that enables an overall club length to be varied without varying the length of the golf club shaft. The system enables a greater number of combinations of club characteristics, such as shaft flex, brand, and length, to be contained within a club fitting cart and/or for a same number of combinations of club characteristics to be contained within a smaller cart.

Abstract: A golf club head includes a heel portion, a toe portion, a hosel, and a striking face. The striking face includes a plurality of scorelines each having an average depth no less than about 0.10 mm, a plurality of micro-grooves each having an average depth no greater than about 0.010 mm, and a plurality of textured surface treatment regions superimposed on the micro-grooves so as to at least partially intersect the micro-grooves.

Abstract: A golf club head includes a heel portion, a toe portion, a hosel, and a striking face. The striking face includes a plurality of scorelines each having an average depth no less than about 0.10 mm, a plurality of first micro-grooves each having an average depth no greater than about 0.010 mm, and a plurality of second micro-grooves overlaid on the first micro-grooves, each of the second micro-grooves having an average depth greater than the average depth of the first micro-grooves. Some embodiments can also have a plurality of textured surface treatment regions superimposed on the overlaid first and second micro-grooves so as to at least partially intersect the micro-grooves.

Abstract: A golf club according to one or more aspects of the present invention may have a mass less than 300 g, a length greater than about 45 inches, a swing weight between D0 and D6, a head weighing less than about 200 g, a club-head volume of at least about 360 cm3, a grip weighing less than about 50 g, and a shaft having a tip end, a butt end, and a shaft balance point located no more than 24 inches from the butt end. The shaft may have a torsional displacement angle greater than about 5.5° and a mass less than about 50 g. A coordinate system having x-, y-, and z-axes may have its origin at the center of gravity of the club head. The golf club head may have a moment of inertia of at least about 4500 g·cm2 about the z-axis and a moment of inertia of at least about 3000 g·cm2 about the y-axis.

Abstract: A golf club head comprises a loft angle no less than 18°, a striking face, a sole portion, and a top portion having an exterior surface. In an imaginary vertical plane spaced from a face center by no more than 10 mm and perpendicular to an imaginary striking face plane, an imaginary line segment has a length of 25 mm, a first endpoint located in the imaginary striking face plane, a second endpoint located above the exterior surface, and forms an angle ? with the striking face plane between 55° and 65°. The line segment is tangent to the exterior surface at a first point. A second point is located on the imaginary line segment and spaced from the first point by no less than 1 mm. The second point is spaced from the exterior surface by a gap distance that is no greater than 0.15 mm.

Abstract: A system for fitting golf clubs to golfers that enables an overall club length to be varied without varying a length of a shaft. The system enables a greater number of combinations of club characteristics, such as shaft flex, brand, and length, to be contained within a club fitting cart and/or for a same number of combinations of club characteristics to be contained within a smaller cart.

Abstract: A golf club head has a main body and a front recess that includes a flange. A rear portion of the main body includes a perimeter-weighting element. A striking face insert is secured within the front recess. A face center is located on the front surface of the striking face insert. A rear cavity is at least partially delimited by the perimeter-weighting element and a rear surface of the striking face insert. A rear insert is secured to the rear surface of the striking face insert. In an imaginary horizontal plane passing through a portion of the rear insert, proximate a heel portion of the club head, a heelwardmost point of the rear insert is spaced further from a vertical center plane than a minimum distance between the flange and the center plane. The club head comprises an auxiliary recess that extends outward from the rear cavity.

Abstract: A golf club according to one or more aspects of the present invention may have a mass less than 300 g, a length greater than about 45 inches, a swing weight between D0 and D6, a head weighing less than about 200 g, a club-head volume of at least about 360 cm3, a grip weighing less than about 50 g, and a shaft having a tip end, a butt end, and a shaft balance point located no more than 24 inches from the butt end. The shaft may have a torsional displacement angle greater than about 5.5° and a mass less than about 50 g. A coordinate system having x-, y-, and z-axes may have its origin at the center of gravity of the club head. The golf club head may have a moment of inertia of at least about 4500 g·cm2 about the z-axis and a moment of inertia of at least about 3000 g·cm2 about the y-axis.

Abstract: A method of selecting a preferred golf shaft for a player who uses an existing golf shaft, according to one or more aspects of the present invention, may comprise gathering a plurality of empirical data sets, each data set corresponding to an individual golf shaft selected from a plurality of golf shafts; providing a plurality of specification codes, each associated with an individual empirical data set of the plurality of empirical data sets; from the plurality of specification codes, identifying a first specification code associated with the existing golf shaft; gathering feedback associated with the existing golf shaft from the player; and using the feedback to select, from the plurality of specification codes, a second specification code corresponding to the preferred golf shaft.