A few key characteristics separate deadlift bars from others, such as powerlifting and olympic weightlifting bars. Although you can technically use all of these to deadlift, they are not all “specialty bars” intentionally designed for deadlifting.  In short, deadlift bars are usually a little longer and narrower than typical barbells. These traits, especially the length and how that length is distributed, tend to give deadlifts bars a bit more flex, also known as whip. The most notable traits that distinguish a deadlift barbell are as follows: Length: Most standard barbells stretch to approximately 86", whereas deadlift bars are longer, reaching about 90". Note that it is not only the entire length of the bar that grows with a typical deadlift barbell, but the distance between the collars as well. This allows the weight to be distributed further toward the edges, contributing to the bar's whip. Diameter: As mentioned above, deadlift bars are often narrower than other barbells. The ideal deadlift bar should be around 27 mm in diameter for the best whip and grip. Reaching 29 mm and above will result in too much stiffness and stray from the best deadlift experience. Knurling: You'll often find that deadlift bars have significantly more "aggressive" knurling. This helps the athlete hold onto the bar through a maximal effort lift, which is critical for the deadlift. As heavy deadlifters know, the grip is often the weak link that breaks in an unsuccessful attempt.