Hardsided Polypropylene 3 Piece Athena TSA Case Luggage Set Color: Lime Polypropylene The Heys USA Athena 3 Piece Hardside Luggage Set contains suitcases made from polypropylene - one of the toughest plastics Each suitcase has a unique 'slate-like' handle system which is push-button released Rigid hard shell that is extremely strong and durable and passed a 400lb impact test The Athena has massive 108mm wheels with protective polypropylene plates Thisset is for someone who has a greater concern about protecting the contents of their luggage from damage - as the Athena weighs a bit more than Heys other luggage lines