Presently, Olympic plates of 10 kilograms (22 lb) or more are 450 millimeters (18 in) in diameter. 450 millimeters (18 in) versions also exist of the lighter 5 kilograms (11 lb) and 2.5 kilograms (5.5 lb) plates to the proper starting position for beginner athletes. These can be aluminum or plastic and may have rubber edges.
As a general rule, powerlifting requires use of stiffer bars to better play the heavier weights being used in the sport. The deadlift barbell is usually the longest, thinnest and the most flexible, thus allowing more weight to be lifted. Powerlifting barbells use simpler, more robust bushings because they do not need to rotate as fast as Olympic weightlifting barbells. Sometimes the sleeves of powerlifting bars are also extended. Additionally, powerlifting bars have their grip marks spaced closer, at 810 millimetres (31.9 in). This closer spacing is used to check legal grip width in the bench press.
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