80mm x 420mm precision machined alloy drums with catridge bearings provide a smooth, quiet ride 80mm diameter alloy roller drum generates natural resistance Alloy frame folds down into 3 parts for convenient storage and transport Wheelbase adjustable from 950mm to 1090mm Each roller contains noise insulator for quiet training Rustproof and lightweight alloy construction Durable urethane belt 8 ground contact points for stability Safety step for easy on and off w/ Step GuardUPC/EAN/GTIN: 4944924406448