A golf club head includes a body defining an interior cavity. The body includes a sole positioned at a bottom portion of the golf club head, a crown positioned at a top portion, and a skirt positioned around a periphery between the sole and crown. The body has a forward portion and a rearward portion. The club head includes a face positioned at the forward portion of the body. In some embodiments, the crown includes a lattice-like structure having thin regions surrounded by a web of relatively thicker regions. In some embodiments, the club head includes one or more stiffening tubes attached between the sole and the crown to improve the acoustic performance of the golf club head.

A golf club head comprises a sole, a recessed sole port in the sole; and a rotatably adjustable sole piece adapted to be at least partially received within the sole port and comprising a central body having a plurality of contact surfaces adapted to contact the sole port and being offset from each other along a central axis extending through the central body of the sole piece. The sole piece can be positioned at least partially within the sole port at five or more rotational and axial positions with respect to the central axis, wherein at each rotational position, at least one of said contact surfaces of the central body contacts the sole port to set the axial position of the sole piece. The sole port and/or the sole piece can be generally pentagonal in shape.

A golf club device for improving one's golf abilities is disclosed. The device includes a head, and a shaft where the head is rotatably connected to at least an upper portion of the shaft. Rotation is achieved with an angular rotation mechanism. The angular rotation mechanism may include a variable resistance feature. The angular rotation mechanism may be positioned in or on the head, or it may be positioned in the shaft. One or more visual alignment indicators may also be employed.

A sleeve 8 fixed to a shaft 6 includes an engaging projection part P1. A head 2 includes an engaging recess part R1. The engaging projection part P1 includes a first side surface P11 located on a side receiving a rotating force by hitting, a second side surface P12 located on an opposite side to the first side surface P11, and an outer surface P13. The engaging recess part R1 includes a first opposed surface R11 opposed to the first side surface P11, a second opposed surface R12 opposed to the second side surface P12, and an inner surface R13 opposed to the outer surface P13. The engaging projection part P1 has a tapered projection part TP1. The part TP1 has a maximum width equal to or greater than an opening width of the engaging recess part R1. The outer surface P13 includes an outer inclination surface K13.

A golf club head includes a body defining an interior cavity. The body includes a sole positioned at a bottom portion of the golf club head, a crown positioned at a top portion, and a skirt positioned around a periphery between the sole and crown. The body has a forward portion and a rearward portion. The club head includes a face positioned at the forward portion of the body. In some embodiments, the crown includes a lattice-like structure having thin regions surrounded by a web of relatively thicker regions. In some embodiments, the club head includes one or more stiffening tubes attached between the sole and the crown to improve the acoustic performance of the golf club head.

A golf club device for improving one's golf abilities is disclosed. The device includes a head, and a shaft where the head is rotatably connected to at least an upper portion of the shaft. Rotation is achieved with an angular rotation mechanism. The angular rotation mechanism may include a variable resistance feature. The angular rotation mechanism may be positioned in or on the head, or it may be positioned in the shaft. One or more visual alignment indicators may also be employed.

Disclosed herein is a golf club head comprising at least one crown opening and at least one crown insert attached to the body and covering the at least one crown opening. The golf club head further comprises at least one sole opening and at least one sole insert attached to the body and covering the at least one sole opening. The golf club head additionally includes at least one weight member configured to clamp first and second ledges at selected locations along a sliding weight track. The golf club head also comprise a coefficient of restitution (COR) feature located on the sole of the golf club head. The at least one crown insert is formed from a composite material having a density between 1 g/cc and 2 g/cc. The at least one sole insert is formed from a composite material having a density between 1 g/cc and 2 g/cc.

A shaft of a golf club includes a reverse-tapered engagement part. The reverse-tapered engagement part includes a sleeve having a reverse-tapered shape, and a reverse-tapered outer surface. A hosel part of a head includes a reverse-tapered inner surface and a hosel slit. A hosel hole includes the reverse-tapered inner surface having a shape corresponding to that of the reverse-tapered outer surface. Either one of the reverse-tapered outer surface and the reverse-tapered inner surface includes an abutting engagement surface and a non-abutting engagement surface. The other of the reverse-tapered outer surface and the reverse-tapered inner surface includes a first abutting surface and the second abutting surface. In the golf club, a first state and a second state in which club lengths are different from each other can be achieved.

A golf club head includes a metal frame having a sole opening, a composite laminate crown joined to the frame, a composite laminate sole insert joined to the frame and overlying the sole opening, and a thermoplastic composite component overmolded on the sole insert. The composite component may include a weight track, ribs, supports or other features. A method of making the golf club includes the steps of forming a frame having a sole opening, forming a composite laminate sole insert, forming a composite laminate crown insert, injection molding a thermoplastic composite head component over the sole insert to create a sole insert unit, and joining the sole insert unit and crown insert to the frame.

A golf club head includes a metal frame having a sole opening, a composite laminate crown joined to the frame, a composite laminate sole insert joined to the frame and overlying the sole opening, and a thermoplastic composite component overmolded on the sole insert. The composite component may include a weight track, ribs, supports or other features. A method of making the golf club includes the steps of forming a frame having a sole opening, forming a composite laminate sole insert, forming a composite laminate crown insert, injection molding a thermoplastic composite head component over the sole insert to create a sole insert unit, and joining the sole insert unit and crown insert to the frame.