Heavy duty, weather-resistant 840 denier and 1000 denier nylon construction. Patented universal mounting system (U.S. Patent #8,011,542 B2) expands from 6" to 14". Removable Neoprene layer is included to protect the bike. Dark colored reflective piping and Tour Master's reflective triangle. Hinged lid provides storage space and easy access to the main compartment.