Teeter-totter (or seesaw) A 10 to 12 foot (3 to 4 m) plank pivoting on a support, much like a child's seesaw. It is constructed slightly off-balance so that the same end always returns to the ground. This is done either by placing the support slightly off-center or else weighting one end of the board. This obstacle also has contact zones. However, unlike the other contact obstacles, the teeter-totter does not have slats. The balance point and the weight of the plank must be such that even a tiny dog, such as a Chihuahua, can cause the high end of the teeter-totter to descend to the ground within a reasonable amount of time, specified by the sanctioning organization's rules (usually about 2 seconds). Smaller dogs get more time to run a course, and this is one reason why it can take them longer than it takes larger dogs.
Right now, as I'm waiting to hear from various job applications, I feel like a teeny tiny dog on a teeter totter, waiting for that high end to lower down to the ground.