TravelCross Luggage 4 Piece Set Expandable w/ TSA lock and Global Tracking System Lightweight durable polyester material 4 piece luggage set: 28" suitcase, 24" suitcase, 20" carry on (all expandable) and one 12 bag (can be attached on the carry on). Both the suitcase and bag are suitable for US airline cabin luggage according to IATA standards Internal trolley system with two wheels TSA-approved keyless LOCK (set by a combination code) and OKOBAN (The Global LOST & FOUND Solution)