An inflation needle, its mold and method of manufacturing same are provided. The inflation needle (10) includes a hollow cylindrical probe (12); a hollow conic base (14) disposed at one end of the hollow cylindrical probe (12); a hollow externally threaded member (16) projected out of the hollow conic base (14), the hollow externally threaded member (16) being distal the hollow cylindrical probe (12) and communicating therewith; and a plurality of handles (18) disposed on an outer surface of the hollow conic base (14).

Embodiments of golf club heads and methods to manufacture golf club heads are generally described herein. In one example, a golf club head may include a body portion with a toe portion, a heel portion, a top portion, a sole portion, a rear portion, and a front portion having a face portion with a face portion thickness extending between a front surface and a back surface. The body portion may be associated with a body portion volume. The golf club head may also include an interior cavity. The interior cavity may include an elastic polymer material including a radiocontrast material. Other examples and embodiments may be described and claimed.

Embodiments of golf club heads, golf clubs, and methods to manufacture golf club heads and golf clubs are generally described herein. In one example, a golf club head includes a recessed opening between a front opening and a back wall portion, a front plate portion coupled to the recessed opening to enclose a first interior cavity in the golf club head between the front plate portion and the back wall portion, a face portion coupled to a front portion to enclose a second interior cavity between the face portion and the front plate portion, a first filler material at least partially filling the first interior cavity, and a second filler material at least partially filling the second interior cavity. The first filler material and the second filler material have at least one different physical property. Other examples and embodiments may be described and claimed.

Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least twenty-eight main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least twenty-eight molds. Each mold of the at least twenty-eight molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of a golf club head that has a volume of at least 100 cm.sup.3.

Methods of manufacturing a golf club head comprising one or more stiffening members proximate the face, and particularly solid rods or a plate with one or more cutouts, is disclosed herein. One method comprises the steps of preparing a wax mold of a golf club head including a plate stiffening member with excess material, casting the golf club head, and machining away the excess material. Another method comprises the steps of casting a golf club body, providing a plate stiffening member, providing a face component such as a face cup, tack welding the plate stiffening member and the face component to the golf club body, and welding these parts together.

A shock absorbing structure of a racket contains: a head and an absorption member matingly contacting with an internal fence of the head. The absorption member is a hollowly tubular structure and covers the internal fence totally. When the head is made of carbon-fiber composite material, the absorption member is made of any one of Thermoplastic Elastomer (TPE), Thermoplastic Rubber (TPR), rubber, Hydrogel, and Thermoplastic Polyurethane (TPU). When the head is made of metal or aluminum alloy, the absorption member is made of any one of Thermosetting Elastomers, Thermoplastic Elastomer (TPE), Thermoplastic Rubber (TPR), rubber, Hydrogel, and Thermoplastic Polyurethane (TPU). When the head and the absorption member are made of different materials, an amplitude of the head is different from an amplitude of the absorption member, and the head interferes the absorption member, thus absorbing vibration.

A putter head including a replaceable intermediate member that can be customized in size, shape, and performance according to user's preference is provided. A putter head according to an embodiment includes a front member having a shaft attachment portion and a front surface constituting a face surface, a rear member attached to a rear of the front member, and an intermediate member that is disposed between the front member and the rear member and is replaceable, and the intermediate member is selectable from a plurality of intermediate members formed in different sizes, shapes, or materials.

A golf club head includes a face, a crown, a sole, and defines a bore that is configured to receive and to selectively retain an elongate weight. The bore is aligned on a longitudinal axis that intersects the face. An elongate weight is insertable into the bore. The elongate weight is rotatable between a first angular position and a second angular position. The golf club head can further include a compliant stop positioned to contact a protrusion of the elongate weight, such that a torque threshold must be overcome to rotate the elongate weight.

Described herein are embodiments of golf club heads with slits and flexure inserts. The slit comprises an opening through the club head body communicating between the exterior of the club head and the hollow interior cavity. The flexure insert can comprise a spring component and a cap. The spring component creates a spring effect within the flexure insert that increases the internal energy of the club head at impact, leading to improvements in ball speed and other golf ball performance characteristics.

A bat includes a handle having a proximate end and a distal end, a barrel having a hollow portion that accommodates the distal end, and a first damping section at least partially sandwiched between the handle and the barrel in the interior of the hollow portion. The first damping section includes a first portion in contact with each of the handle and the barrel in the interior of the hollow portion, and a second portion disposed closer to the proximate end than the first portion, the second portion being in contact with an inner peripheral surface of the barrel and not being in contact with an outer peripheral surface of the handle. In a cross section along a center axis of the barrel, the barrel has a depression depressed relative to the inner peripheral surface in the cross section, the second portion has a protrusion fitted in the depression.