Provided is a golf shaft capable of realizing a sufficient low trajectory and low spin. The golf shaft has a rigidity distribution in which rigidity is gradually increased from a tip end section to a butt end section, and, in the rigidity distribution, has an intermediate point at which inclination is changed in an intermediate section between the tip end section and the butt end section, a difference in rigidity between the tip end section and the intermediate point is 3.00 kgf.Math.m.sup.2-5.00 kgf.Math.m.sup.2, and a difference in rigidity between the intermediate point and the butt end section is 2.00 kgf.Math.m.sup.2or less.

Provided is a golf shaft capable of realizing a sufficient low trajectory and low spin. The golf shaft has a rigidity distribution in which rigidity is gradually increased from a tip end section to a butt end section, and, in the rigidity distribution, has an intermediate point at which inclination is changed in an intermediate section between the tip end section and the butt end section, a difference in rigidity between the tip end section and the intermediate point is 3.00 kgf.Math.m.sup.2-5.00 kgf.Math.m.sup.2, and a difference in rigidity between the intermediate point and the butt end section is 2.00 kgf.Math.m.sup.2or less.

A golf club shaft having a weight distribution such that the balance point percentage is less than or equal to 44.50%. The weight distribution of the shaft allows for an increase in length and/or club head weight of a golf club while having a reduced impact on the swing weight.

A constrained frequency resonator is incorporated into the shaft of a striking implement for transferring and, advantageously, amplifying momentum from a striking end to a gripped end of the striking implement, thereby amplifying the sensation of a strike felt at the gripped end. The resonator has a substantially hourglass shape, with wide ends and a narrow waist, and is made of stainless steel or another very hard material. The shape of the resonator causes it to act as a vibration frequency filter that transfers and, preferably, amplifies a certain frequency or band of frequencies. The striking implement may be a golf club, pool cue, or other implement in which frequency transfer to a gripping section is desired.

A constrained frequency resonator is incorporated into the shaft of a striking implement for transferring and, advantageously, amplifying momentum from a striking end to a gripped end of the striking implement, thereby amplifying the sensation of a strike felt at the gripped end. The resonator has a substantially hourglass shape, with wide ends and a narrow waist, and is made of stainless steel or another very hard material. The shape of the resonator causes it to act as a vibration frequency filter that transfers and, preferably, amplifies a certain frequency or band of frequencies. The striking implement may be a golf club, pool cue, or other implement in which frequency transfer to a gripping section is desired.

A golf club 100 includes a head 200 having a hosel part 202, a shaft 300, and a reverse-tapered engagement part RT. The reverse-tapered engagement part RT includes a sleeve 400 having a reverse-tapered shape and being fixed to a tip portion of the shaft 300, and a spacer fitted outside of the sleeve 400. The hosel part 202 includes a hosel hole 204 and a hosel slit 206 which is provided on a side of the hosel hole 204 and enables the shaft 300 to pass through the hosel slit. The hosel hole 204 has a reverse-tapered hole 205 having a shape corresponding to a shape of an outer surface of the reverse-tapered engagement part RT. The reverse-tapered engagement part RT is fitted to the reverse-tapered hole 205. A club length is changed by changing a wall thickness of the spacer.

A bendable core insert configured for manufacturing a golf-club shaft. The bendable core includes a bendable relief tube having a first end attached to a top coupling tube and a second end attached to a bottom coupling tube. The bendable relief tube, the top coupling tube, and the bottom coupling tube have respective channels that are aligned to form a continuous channel through opposing ends of the bendable core insert. The length of the bendable core insert corresponds to a length of a corresponding segment of the golf-club shaft. The bendable relief tube is configured to be bent in one or more directions to define a bend profile of the corresponding segment of the golf-club shaft.

A golf club (2) comprising a shaft (20), a head and a damping device (1, 100). The damping device (1, 100) includes an anchor element (3, 103) and a damping element (4, 104) interconnected by a rigid rod (5, 105). The anchor element (3, 103) is anchored within the lower section of the shaft (20) that has a substantially constant diameter such that the damping element (4, 104) is in contact with an internal surface of the shaft (20) to dampen vibrations therein.

A golf club (2) comprising a shaft (20), a head and a damping device (1, 100). The damping device (1, 100) includes an anchor element (3, 103) and a damping element (4, 104) interconnected by a rigid rod (5, 105). The anchor element (3, 103) is anchored within the lower section of the shaft (20) that has a substantially constant diameter such that the damping element (4, 104) is in contact with an internal surface of the shaft (20) to dampen vibrations therein.

A shaft 6 includes a tip end Tp and a butt end Bt. If a shaft length is defined as Ls, a distance between the butt end Bt of the shaft and a center of gravity G of the shaft is defined as Lg, and a ratio of the distance Lg to the shaft length Ls is defined as a ratio of the center of gravity of the shaft, then the ratio of the center of gravity of the shaft is equal to or less than 47%. The shaft length Ls is equal to or less than 991 mm. If a forward flex is defined as F1 (mm) and a backward flex is defined as F2 (mm), a flex point ratio C1 of the shaft calculated by the following formula (1) is equal to or less than 39%:

C1=[F2/(F1+F2)]100](1).