These are the massive weight plates & barbell you see on the TV when you're watching the professional weightlifters lift those awesome weights, those very large weights are Olympic sized weights & that's exactly what your buying here the big Olympic weight plates & Olympic sized barbell to go with it, you get 4x 5kg, 4x 10kg & 4x 15kg weight plates. That is 12 Olympic size weight plates to go on the 20kg Olympic sized 2.2m long barbell which is included & makes up part of the weight in the set. The Olympic plates are Tri-Grip Plates they are made from environmentally friendly cast iron that is painted with durable Hammerton & have 3 holes & rounded edges on the grips to make handling them more pleasant, The barbell is a standard-sized Olympic barbell with a bar diameter of 50mm to fit the standard sized Olympic plates with a hole diameter of 52mm so you can use this Olympic weight set with any other Olympic barbells or weight plates that you may have & they will all fit