A golf swing training club comprising: (a) a shaft; (b) a golf head attached to a first, lower end of the shaft; and (c) a handgrip attached to a second, upper end of the shaft; wherein a standard longitudinal shaft bending angle (β) of the shaft is within a range of 45° to 90°; and wherein a mechanical beam portion of the golf swing training club is characterized by a standard extensive shear modulus of at most 15°.

A golf swing training club comprising: (a) a shaft; (b) a golf head attached to a first, lower end of the shaft; and (c) a handgrip attached to a second, upper end of the shaft; wherein a standard longitudinal shaft bending angle (β) of the shaft is within a range of 45° to 90°; and wherein a mechanical beam portion of the golf swing training club is characterized by a standard extensive shear modulus of at most 15°.

A shoulder rotation clip as a putting trainer to assist a golfer in repetitive drills to improve the skills necessary to strike a golf ball in a straight manner and drop the ball into the hole on a putting green. The shoulder rotation clip is used in conjunction with existing alignment rods to prevent twisting of the wrists and arms to improve a golfer's putting stroke.

Provided is a golf shaft comprising an element tube made of steel, a plating layer formed on an outer periphery of the element tube, an outer layer covering the plating layer, an adhesive layer interposed between the plating layer and the outer layer to bond between the plating layer and the outer layer. The outer layer is formed of a fiber reinforced plastic having a matrix resin that is an epoxy resin, and the adhesive layer is an epoxy resin composition or a carbon nano tube resin composition, the epoxy resin composition comprising an epoxy resin and a mixed curing agent in which two or more kinds of amine-based curing agents are mixed, and the carbon nano tube resin composition comprising an epoxy resin and at least one kind of curing agents as well as dispersed carbon nano tubes.

Provided is a golf shaft comprising an element tube made of steel, a plating layer formed on an outer periphery of the element tube, an outer layer covering the plating layer, an adhesive layer interposed between the plating layer and the outer layer to bond between the plating layer and the outer layer. The outer layer is formed of a fiber reinforced plastic having a matrix resin that is an epoxy resin, and the adhesive layer is an epoxy resin composition or a carbon nano tube resin composition, the epoxy resin composition comprising an epoxy resin and a mixed curing agent in which two or more kinds of amine-based curing agents are mixed, and the carbon nano tube resin composition comprising an epoxy resin and at least one kind of curing agents as well as dispersed carbon nano tubes.

A shaft includes a plurality of fiber reinforced layers. The fiber reinforced layers include a plurality of hoop layers and a plurality of straight layers. The straight layers include at least one full length straight layer. At least two of the hoop layers and at least two of the straight layers constitute an alternate lamination of the hoop layers and the straight layers. The hoop layers may include a first butt partial hoop layer and a second butt partial hoop layer that is longer in an axial direction than the first butt partial hoop layer. The first butt partial hoop layer may have a weight per unit area of greater than that of the second butt partial hoop layer.

A shaft includes a plurality of fiber reinforced layers. The fiber reinforced layers include a plurality of hoop layers and a plurality of straight layers. The straight layers include at least one full length straight layer. At least two of the hoop layers and at least two of the straight layers constitute an alternate lamination of the hoop layers and the straight layers. The hoop layers may include a first butt partial hoop layer and a second butt partial hoop layer that is longer in an axial direction than the first butt partial hoop layer. The first butt partial hoop layer may have a weight per unit area of greater than that of the second butt partial hoop layer.

A golf club shaft includes a tip end, a butt end, a first anisotropic portion that is twisted in a first direction in conjunction with a bending of the golf club shaft at a circumferential bending position, and a second anisotropic portion that is twisted in a second direction in conjunction with the bending. The second anisotropic portion is located on a tip end side relative to the first anisotropic portion. The second direction is opposite to the first direction. In the shaft, the twist accompanied by the bending in the first anisotropic portion can be offset by the twist accompanied by the bending in the second anisotropic portion.

A golf club shaft includes a tip end, a butt end, a first anisotropic portion that is twisted in a first direction in conjunction with a bending of the golf club shaft at a circumferential bending position, and a second anisotropic portion that is twisted in a second direction in conjunction with the bending. The second anisotropic portion is located on a tip end side relative to the first anisotropic portion. The second direction is opposite to the first direction. In the shaft, the twist accompanied by the bending in the first anisotropic portion can be offset by the twist accompanied by the bending in the second anisotropic portion.

A shaft for a putter includes decorative sheaths that may beautify the shaft while retaining lightweight stiffness and avoiding breaking the sheaths.