The portable E-Z Rise Cattle Guard installs on any level surface (requiring no pit to dig and maintain). At full rise, the middle of the unit's Flex-Floor is 13 inches above the ground, which prevents animals from attempting to pass through. When driven over, the floor collapses under the vehicle's weight, coming to rest on the ground. Once crossed, the floor returns to its original 13-inch full-rise height within 25-30 seconds after exiting. Because the ground bears the weight (not pipes over a pit), the unit can support extremely heavy loads