Trifold, or triple fold, ramps fold in three locations to make the ramp take up only a quarter of its area when fully expanded. Stairs, high thresholds, and other height obstructions will trouble you no more with a sturdy, compact trifold ramp, and they're also very helpful for getting in and out of vehicles. Make sure that the ramp you select is light enough for you or a caretaker to carry, though; if these ramps are unmanageable, you may want to look into single fold ramps or even a vehicle lift for your mobility device.