Golf club having double-walled striking face

A golf club comprising:

• a topline;
• a striking face attached to the topline;
• a back portion attached to the topline;
• a sole attached to the back portion;
• and
• an inner wall structure at least partially in contact with a rear surface of the striking face, the inner wall structure configured to slide against the rear surface of the striking face, wherein the sole, the inner wall structure, and the rear surface of the striking face define a sole channel, the sole channel separating a portion of the sole from the striking face.

A golf club head comprising:

• a striking face having a top edge attached to a topline and a bottom edge proximate the bottom of the face;
• a back portion attached to the topline;
• a sole portion attached to the back portion, the sole portion including a sole channel;
• and
• an inner wall structure, the inner wall structure having:
• a fixed end attached to the sole portion;
• an unfixed end disposed in a recess defined by an inner surface of the topline;
• a contact portion attached to the unfixed end and in contact with a rear surface of the striking face;
• and
• a support portion attached to the fixed end and not in contact with the rear surface of the striking face.