Weight plates come in two different sizes, standard or olympic, standard plates have a 1 inch in the center and olympic have a 2 inch hole, we feature borth ranges in sets that can be combined with gym machines or weight benches but it's important to ensure that you invest in the right size to fit whichever machine you're looking to combine them with. If you need help deciding on the right option please feel free to call us on 0845 459 4500 for advice.