Dynamic Gold AMT Tour Issue irons shafts have the same performance DNA as Dynamic Gold and are designed to get progressively heavier as golfers move from their long iron to short iron. Lighter long irons produce increased speed and higher initial launch, which makes them easier to swing and deliver a softer landing. The Tour-weighted short irons produce traditional Dynamic Gold accuracy, consistency and trajectory. AMT stands for Ascending Mass Technology, which means the steel shaft's weight increases in 3 gram increments from the 3-iron to PW, while the balance point is adjusted so that the swing weight is consistent to standard Dynamic Gold throughout the set.