Callaway I-Trax Putter. The I-TRAX putter from Callaway uses the latest technology to give superb feel and control. Interchangable vision strips are provided with the I-TRAX putter to give the golfer the choice of alignment aids. Each of these vision strips extends the intended line of the putt making it much easier for your eye to make a stroke down the correct line. The head of the Callaway I-TRAX has been precision milled from aluminum to give a solid feel with plenty of feedback. A black anodized finish is then added to the head to give a stylish look and prevent wear and corrosion. A 'Sound Slot' is milled into the head behind the face to give the perfect sound when struck. Two brass weights have been inserted into the face and an aluminum weight is inserted into the sole of the putter. These weights are fixed and give the perfect centre of gravity for a true and consistent roll and superb stability through impact.