The Yakima 1A Complete Rain Gutter Mounted Car Roof Rack is specifically designed to fit vehicles with rain gutters or installed artificial rain gutters. The 1A Towers are made with tough Zytel nylon. The bottom of the round bar is 5.5 inches above the rain gutter and the overall height is 7.25" above the rain gutter. The complete 1A Rain Gutter Rack includes 4 towers, 2 round bars and 4 round bar end caps. Yakima's recommended round bar length for your vehicle will be sent unless otherwise specified in the "Additional Comments" box during checkout. Longer round bar lengths are available upon request. Yakima round bars tend to create different levels of wind noise depending on the vehicle application, using Yakima's Wind Fairing (sold separately) will drastically reduce the wind noise. Yakima SKS Lock Cores are recommended to lock the rack to your vehicle (sold separately).