51mm diameter hole so that they will fit all olympic bars Weight Plate for this Set: 25kg x 2 - Steel (Iron) Weight Plate coated with a grey hammertone finish Bar Weight: 16kg - Standard 51.5mm hole suitable for all 50mm diameter barbells Max Load: 250kg - Solid construction and effective in design, the Standard Olympic Bar is made for everyday gym use, and designed for a snug fit in the hand. Featuring heavy duty structural integrity, the Standard Olympic Bar is built to take a pounding and help you expand your range of exercises Spin Lock Collar: 2 Steel (Iron) Weight Plate coated with a grey hammertone finish. Standard 51.5mm hole suitable for all 50mm diameter barbells. Each Weight Plate has triple grip handles (tri-grip plate). EZ for being used as hand weight Training method. Solid construction and effective in design, the Standard Olympic Bar is made for everyday gym use, and designed for a snug fit in the hand. Featuring heavy duty structural integrity, the Standard Olympic Bar is built to take a pounding and help you expand your range of exercises