Dumbells are used for weight training. Dumbells are of three types - Adjustable, Selectorized and Fixed Weight. In an adjustable dumbell weight plates slip into either side of a rod and and fixed with large nuts. Fixed weights are shaped as dumbells in cast iron. For more comfort they also come in neoprene, rubber or in a plastic shell filled with concrete.
Selectorized dumbells are come with a stand and use a dial to select the number of plates that will attach to the handle when lifted.
Barbells come from 4Ft to 8Ft. Powerlifters usually use bars over 7.2 Ft and are not so common. The surface of the bar will have a crosshatch pattern for better grip.
Stiffer bars are used in powerlifting as an olympic sport. More length is required to add more plates and the thickness is increased so it does not deform with use. An Olympic bar for men is 2.2 metres (7.2 ft) long and weighs 20 kilograms (44 lb). The outer ends are 50 millimetres (2.0 in) in diameter, while the grip section is 28 millimetres (1.1 in) in diameter, and 1.31 metres (4.3 ft) in length.
Bumper plates are used in power lifting . It is important that they can safely be dropped from head height hence the word " bumper" . They are usually coated in rubber.
EZ curl bars are used for bicep curls, upright rows and lying tricep extensions. They are used for a more neutral and less supinated position.