Plate loaded strength machines require the use of conventional round plates, the same plates you find on barbells. These plates are hung on the machine and while they generally have limits, plate loaded machine maximum weights generally far exceed those of selectorized equipment. On the other end of the spectrum, plate loaded machines can also use far lighter weights than the minimum weights on selectorized machines. A positive aspect is that plate loaded strength equipment is usually much more cost effective than selectorized machines. Gym owners do not need to buy a set of weight plates for every single machine as opposed to selectorized machines where the owner has to pay for each weight stack on every machine.