1200-denier Technolast water-resistant, UV-treated polyester construction. Large main compartment and two smaller side pockets. Unique anchor knot attachment system features anti-slip cam buckles. Anti-scratch base. Rain cover with pocket. Installs over the passenger seat and part of the tail section; fits bikes with a tail section width of 10.2″ or less. Measures 15″ L x 27″ W (front; 20″ rear) x 16″ H (from top of bag to bottom of overlapped sides); 7″ H from top of bag to seat in front (5″ in rear).