A putter head comprising a back portion and a front portion, the front portion being of substantially lower density material than the back portion and said front portion superimposing said back portion and defining substantially the entire striking face of the putter. In one embodiment, a carbon-based polymer is deposited on top of an interconnect metal line in the semiconductor die where relatively large power dissipation is known to occur. An image forming apparatus further includes a first mechanism that causes the first unit and the second unit to move toward or away from each other, a moving member that moves the first mechanism, and a second mechanism that causes the second unit and the third unit to move toward or away from each other in conjunction with a movement of the first mechanism. A tracking circuit, including a monitoring function, tracks drift in the parameter by monitoring a feedback signal that has a characteristic that correlates with drift in the communication channel, and updates, or indicates the need for updating of, the operation value of the parameter in response to the monitoring function. Each roll forming station includes upper and lower roll forming pairs, which cooperate for forming the flange or portion thereof.