Abstract: 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. The channel may have a cross-sectional profile that is asymmetric with a front wall and a rear wall where the front wall is longer than the rear wall. The channel may also have a center thickness that is different than a thickness at the heel and toe sides.

Abstract: A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball where the face has multiple thickness regions. The face has a center region, an upper region, a lower region, a toe region, and a heel region. The upper and lower regions have a ramped thickness extending from a center region to an upper and lower edge of the face. The heel and toe regions have a constant face thickness and have a thickness less than the other regions. Additionally, the club head body has a flange where the face is welded to the club head body. The flange has a thickness that is greater than the thickness of the heel and toe regions of the face.

Abstract: A golf club head has a body defining a ball striking face. The body further has a rear portion comprising a plurality of side walls and a planar lower portion. The plurality of side walls extend downward from a top of the golf club head towards the planar lower portion. The body further comprises a cover extending over the rear. The body further defines a gap between the cover and the planar portion.

Abstract: An organic light emitting device including an anode; a hole transport region on the anode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a cathode on the electron transport region, wherein the hole transport region includes: a first hole transport layer including a first hole transport material represented by the following Formula 1 or a second hole transport material represented by the following Formula 2; and a second hole transport layer on the first hole transport layer, the second hole transport layer including a third hole transport material represented by the following Formula 3 or a fourth hole transport material represented by the following Formula 4:

Abstract: An organic light emitting device including an anode; a hole transport region on the anode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a cathode on the electron transport region, wherein the hole transport region includes: a first hole transport layer including a first hole transport material represented by the following Formula 1 or a second hole transport material represented by the following Formula 2; and a second hole transport layer on the first hole transport layer, the second hole transport layer including a third hole transport material represented by the following Formula 3 or a fourth hole transport material represented by the following Formula 4:

Abstract: 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. The channel may have a cross-sectional profile that is asymmetric with a front wall and a rear wall where the front wall is longer than the rear wall. The channel may also have a center thickness that is different than a thickness at the heel and toe sides.

Abstract: 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.

Abstract: A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball where the face has multiple thickness regions. The face has a center region, an upper region, a lower region, a toe region, and a heel region. The upper and lower regions have a ramped thickness extending from a center region to an upper and lower edge of the face. The heel and toe regions have a constant face thickness and have a thickness less than the other regions. Additionally, the club head body has a flange where the face is welded to the club head body. The flange has a thickness that is greater than the thickness of the heel and toe regions of the face.

Abstract: A golf club head has a body defining a ball striking face. The body further has a rear portion comprising a plurality of side walls and a planar lower portion. The plurality of side walls extend downward from a top of the golf club head towards the planar lower portion. The body further comprises a cover extending over the rear. The body further defines a gap between the cover and the planar portion.

Abstract: 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.

Abstract: 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. The channel may have a cross-sectional profile that is asymmetric with a front wall and a rear wall where the front wall is longer than the rear wall. The channel may also have a center thickness that is different than a thickness at the heel and toe sides.

Abstract: An organic electroluminescence device in which a polycyclic compound including an electron donor and an electron acceptor is included in an emission layer is provided. The electron donor contains an acridine derivative or a dibenzo-azasiline derivative, and the electron acceptor contains B as a ring-forming atom, O or S directly bonded to B, and a heterocyclic group in which three or five hexagonal rings are condensed. Accordingly, an organic electroluminescence device having high efficiency may be achieved.

Abstract: 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. The channel may have a cross-sectional profile that is asymmetric with a front wall and a rear wall where the front wall is longer than the rear wall. The channel may also have a center thickness that is different than a thickness at the heel and toe sides.

Abstract: An organic electroluminescence device includes a first electrode, a second electrode on the first electrode, and an emission layer between the first electrode and the second electrode. The emission layer may include a compound including a first phenyl group that is substituted with at least one cyano group and a second phenyl group that is substituted with five substituted or unsubstituted carbazole groups, the second phenyl group being directly bonded to the first phenyl group.

Abstract: A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball where the face has multiple thickness regions. The face has a center region, an upper region, a lower region, a toe region, and a heel region. The upper and lower regions have a ramped thickness extending from a center region to an upper and lower edge of the face. The heel and toe regions have a constant face thickness and have a thickness less than the other regions. Additionally, the club head body has a flange where the face is welded to the club head body. The flange has a thickness that is greater than the thickness of the heel and toe regions of the face.

Abstract: 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.

Abstract: An organic light emitting device including an anode; a hole transport region on the anode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a cathode on the electron transport region, wherein the hole transport region includes: a first hole transport layer including a first hole transport material represented by the following Formula 1 or a second hole transport material represented by the following Formula 2; and a second hole transport layer on the first hole transport layer, the second hole transport layer including a third hole transport material represented by the following Formula 3 or a fourth hole transport material represented by the following Formula 4:

Abstract: A golf club head has a body defining a ball striking face. The body further has a rear portion comprising a plurality of side walls and a planar lower portion. The plurality of side walls extend downward from a top of the golf club head towards the planar lower portion. The body further comprises a cover extending over the rear. The body further defines a gap between the cover and the planar portion.

Abstract: A golf club head has a body defining a ball striking face. The body further has a first leg extending away from the ball striking face and a second leg extending away from the ball striking face wherein a void is defined between the first leg and the second leg. The body further defines a cover that extends over the void. The golf club head may further have support structures and adjustable weight members.

Abstract: 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.