The Navi-Trac Frame Tent System incorporates modular construction in which fabric panels slide through channeled-beams for faster, simplified installations, smooth, weathertight fit and maximum stability. This engineered, certified frame tent system is available in 30′ and 40′ widths. Navi-Trac uprights adjust from 8′ to 10′. The 40′ unit features one piece rafters with 10′, 15′ and 20′ bays.