The unique dynapack is the perfect solution for those who dont want a handlebar bag or full quicktrack system but occasionally need more capacity than an under seat bag constructed of molded 600 denier for a sleek aerodynamic profile the dynapack easily holds tools inner tubes and other essentials with room to spare for a light rain jacket small picnic lunch or anything else you might need a light weight aluminum exo frame holds the dynapack securely while a quick release seatpost mount