Diameter: 450mm Collar opening: 50.6mm Plate thickness 2.5kg: 18mm 5kg: 35mm Sold in PAIRS Recommended for use on rubber gym flooring or lifting platforms If you're starting out in weightlifting or you teach others, the 360 Strength 2.5kg Technique Plates are exactly what you're looking for. Made from a hard plastic resin, they are light weight, super tough, and completely droppable. Identical in size to bumper plates, the standardised diameter allows the teaching of technique without the adding the heavier weight of actual bumper plates, but does not impact the dynamics of pulling from the floor as a smaller diameter plate would. Specifications: Technique Bumper Plates – available in 2.5kg (sold in pairs) Diameter: 450mm Collar opening: 50.6mm 2.5kg: 18mm 5kg: 35mm Color 2.5kg: Red 5kg: Black Recommended for use on rubber gym flooring or lifting platforms