OLYMPIC BARBELLS MEN’SSPECIFICATIONS & FEATURES:WEIGHT: 20KG, BEARING: 1000LB/1500LB;MATERIAL: SPRING STEEL;SIZE: 2200X28MM;4 NEEDLES/10 NEEDLES, 2 COOPER SLEEVES;HARD CHROME PLATING (0.03mm~0.04mm Chrome Thickness);IWF STANDARD KNURLING, 6 SECTIONS KNURLING (Depth 0.25mm~0.35mm);150KPS/190~200KPS, NK BEARING.WEIGHT TOLERANCE:+/-10 GRAMS.