An Olympic weightlifting bar 20kg is a men's competition barbell manufactured to IWF (International Weightlifting Federation) specifications, designed for snatch and clean & jerk. The shaft diameter is precisely 28mm (±0.03mm), providing the optimal balance of whip (flexibility) and torsional rigidity. The bar has a tensile strength of 190,000-220,000 psi, heat-treated to resist permanent bending under 1,000+ lb loads. The distance between collars is 1302mm (51.25 inches), with an overall length of 2200mm (86.6 inches). The sleeves are 50mm diameter, chrome-plated, and feature needle bearings (usually 10-12 bearings per sleeve) for low-friction rotation during the catch phase—critical for saving the wrists and elbows. Knurling is moderate (18-20 TPI) with a center knurl (200mm wide) for grip during front squats, and IWF-specified knurl marks (rings at 810mm and 1220mm from the center). The bar finish is typically hard chrome (most durable, no rust), although some manufacturers offer black oxide or zinc (less expensive, rust-prone). The whip (deflection under load) is engineered: a 20kg bar loaded with 200kg deflects 5-7mm at the center, storing elastic energy that assists the lifter's extension. Weight accuracy is ±10g for IWF-certified bars. The bar is not intended for powerlifting (where 29mm diameter bars are preferred) or for heavy deadlifts in a commercial gym (the whip increases range of motion). Maintenance includes cleaning chalk from knurling with a nylon brush and applying 3-in-1 oil to a rag (never directly on knurling) to prevent rust. Needle bearings require no lubrication—the sealed cartridge bearings are maintenance-free. For home gyms, a 20kg weightlifting bar is appropriate for lifters proficient in snatch/clean & jerk. For general strength training, a 28.5mm multipurpose bar is more versatile.