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 may include a body portion having an interior cavity, a front portion, a rear portion, a toe portion, a heel portion, a sole portion, and a top portion. A face portion may be coupled to the front portion and may include a front surface having a plurality of grooves with each groove extending in a first direction, and a back surface having a plurality of channels with each channel having a length and a width being substantially smaller than the length. A filler material may at least partially fill the interior cavity. The length of at least one channel of the plurality of channels may extend in a second direction different from the first direction. Each channel may be at least partially filled with the filler material and may be configured to engage the filler material to adhere the filler material to the back surface of the face 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 with an interior cavity and a face portion attached to the body portion to enclose the interior cavity. The golf club head also includes a filler material in the interior cavity and attached to the back surface of the face portion. The golf club head also includes an internal mass portion in the interior cavity spaced apart from the body portion and attached to the filler material. The filler material may be located between the face portion and the internal mass portion. The internal mass portion may be movable in the interior cavity relative to the body portion and the face portion. Other examples and embodiments may be described and claimed.

Described herein are embodiments of golf club heads having a balance of the following parameters: a low and back club head center of gravity position, a high moment of inertia, a large Ixy product of inertia, and low aerodynamic drag. Methods of manufacturing the embodiments of golf club heads having a balance of club head center of gravity position, moment of inertia, product of inertia, and aerodynamic drag are also described herein.

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 top portion, a sole portion, and a back portion. The back portion may be include a back wall portion. The golf club head may also include a face portion, an interior cavity, at least one weight portion, and at least one port. The interior cavity may be partially or entirely filled with a polymer material. Other examples and embodiments may be described and claimed.

Embodiments of golf club heads with energy storage characteristics are presented herein. In some embodiments, a golf club head comprises a hollow body comprising a strikeface, a heel region, a toe region opposite the heel region, a sole, a top rail and an inflection point. The inflection point provides increase bending of the strikeface thereby providing performance enhancement over clubs without an inflection point.

Golf club heads with ribs are described herein. A golf club head comprises a first rib protruding from an internal surface of the club head, and a second rib protruding from the internal surface of the club head. The first rib and the second rib can comprise a varying height. The club head further comprises a connecting rib extending between the first rib and the second rib to connect the first rib and the second rib together. The connecting rib can comprise a varying height. In another embodiment, the club head can comprise a first connecting rib and a second connecting rib extending between the first rib and the second rib. The ribs provide structural support and sound control for the club head.

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 a front portion, a rear portion, a toe portion, a heel portion, a top portion, and a bottom portion. The golf club head may include a sealed cavity located behind a face portion. A polymer insert and a filler material may be contained within the sealed cavity. Other examples and embodiments may be described and claimed.

A method for manufacturing a golf club head including a golf club head body, a striking face, and an inner wall supporting the striking face. A ledge extends from a body into the interior of the golf club head body, and the inner wall is disposed within a gap between the striking face and the ledge. A rear surface of the inner wall is supported by a portion of the golf club head body, and a rear surface of the striking face is in contact with a portion of the inner wall. The inner wall may be inserted into the golf club head through an opening defined in the toe portion of the golf club head or the rear portion of the golf club head.

A marking system for a baseball bat includes a bat including a barrel extending along a central longitudinal axis, the barrel defining a minimal vibration region. The marking system also includes a sheet having a first edge, a second edge positioned opposite the first edge, a third edge positioned between the first and the second edges, and a fourth edge positioned opposite the third edge, the first edge having a first curvature and the second edge having a second curvature, the sheet adapted to at least partially encircle a portion of the barrel of the bat. Additionally, a first positioning feature is disposed on the sheet, and a first alignment feature is disposed proximate the first edge of the sheet. Furthermore, the first positioning feature may be configured to be positioned adjacent to at least a portion of the minimal vibration region.

A golf club head including a crown, a sole, a hosel, a face and a flexure. The flexure provides compliance during an impact between the golf club head and a golf ball, and is tuned to vibrate, immediately after impact, at a predetermined frequency.