A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball and a channel extending across a portion of the sole. The channel may be recessed from adjacent surfaces of the sole and have a depth of recession from the adjacent surfaces of the sole. A pair of ribs are positioned within the channel. The ribs may diverge away from one another and may have a first rib located in a toe portion of the channel and a second rib located in the heel portion of the channel.

A golf club head of the wood-type, including a body having a ball-striking face and a sole, is disclosed. The sole can include a wave slot for adding additional weight to the golf club head and for providing improved performance. The wave slot can include a front sidewall, a rear sidewall, and at least two waves. The waves can be positioned between the front and rear sidewalls and can each include a valley portion at the lowest point of the wave such that the valley portion does not protrude below the sole.

A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball and a channel extending across a portion of the sole. The channel may be recessed from adjacent surfaces of the sole and have a depth of recession from the adjacent surfaces of the sole, wherein the channel comprises a center portion extending across a center of the sole, a heel portion extending from a heel end of the center portion toward the heel, and a toe portion extending from a toe end of the center portion toward the toe, wherein the width and the depth of the center portion of the channel are substantially constant, and wherein the depth of the channel is greater at the heel and toe portions than at the center portion.

A golf club head includes a rear body having a crown member coupled to a sole member, and a front body coupled to the rear body to define a substantially hollow structure. The front body includes a strike face and a surrounding frame that extends rearward from a perimeter of the strike face. At least a portion of an outer wall of the club head comprises a thermoplastic composite having a plurality of lamina layers. The plurality of lamina layers include at least a fabric reinforced thermoplastic composite layer and a filled thermoplastic layer, and the fabric reinforced thermoplastic composite layer and the filled thermoplastic layer are directly bonded to each other without an intermediate adhesive.

A hollow golf club head includes a metallic front body coupled with a composite rear body. The front body includes a strike face and a surrounding frame that extends rearward from a perimeter of the strikeface. The rear body includes a crown member coupled with a sole member. The sole member can have a structural layer formed from a filled thermoplastic material. The crown member can have structural layer and/or a resilient layer. The structural and resilient layers can be formed from fiber-reinforced thermoplastic composite material. The sole member has an opening through which a metallic weight pad at least partially extends. The weight pad is bonded to the structural layer and includes an aperture for attaching a metallic weight.

A golf club head comprises a body having a face, a crown and a sole together defining an interior cavity. The body having a head-shaft connection system, a rear weight fastened to the golf club head proximate the rear end of the club head and proximate the Y-Z plane, and a front weight port or an internal cap connection system for securing the rear weight; in combination with specific windows regarding the moments of inertia and center of gravity.

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 having an interior cavity and a front portion. The golf club head may include a face portion on the front portion and having a front surface and a back surface with a center portion and a perimeter portion at least partially surrounding the center portion. The golf club head may include a face bracket portion having at least one bracket arm with end portions attached to the perimeter portion. The golf club head may further include a face insert portion located between and coupled to the back surface of the face portion and to the face bracket portion. 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 body portion comprising a material having a first density and an interior cavity having a filler material therein comprising a material having a second density. The golf club head also includes a first mass portion coupled to the body portion and a second mass portion coupled to the hosel portion. The first mass portion and the second mass portion comprise a material having a third density. A port on the body portion is configured to receive the first mass portion. At least a portion of the first mass portion is below a horizontal midplane of the body portion. The first density is greater than the second density. The third density is greater than the first density. A distance between a portion of the first mass portion and the hosel portion is substantially greater than a distance between the portion of the first mass portion and the toe portion edge. The first mass portion and the second mass portion have at least one different physical property. Other examples and embodiments may be described and claimed.

A golf club head comprising a body and a plurality of stiffening members, the tension or compression of which can be adjusted, is disclosed herein. The body comprises a face section, a sole section, and a crown section or a return section, and also defines a hollow interior. Each of the plurality of stiffening members is at least partially disposed within the hollow interior, and extends from the crown section or return section to the sole section to reduce stresses placed on the face during impact with a golf ball. The compression or tension of the stiffening members may be adjusted to affect the stresses experienced by the golf club head upon impact with a golf ball.

A ball striking device may include a ball striking plate having a front surface configured to strike a ball and a rear surface opposite the front surface. The ball striking device may include a covering element located behind the rear surface. The covering element may be affixed to the rear surface of the ball striking plate with an adhesive member. The adhesive member may include a double-sided tape. Further, a thickened portion of the ball striking plate may be located behind a desired-contact region of the ball striking plate and the covering element may be affixed thereto. The covering element may be a highly-contoured element. The ball striking device may be a golf club head.