The two models divide along player type. The Series 1 uses a muscle-cavity back with structural mesh and internal tungsten weighting, and McLaren positions it for better players who prioritize control, feel and consistency. The Series 3 is MIM'd (Metal Injection Molding) with a carbon-fiber bonnet and a heel-cut sole for players who want performance and forgiveness in a distance-style iron. Both are available 4-PW in right-hand.