Elev8 -- The Mobility Project

Allow a safe, gradual entrance in and out of most doorways.
The self-supporting adjustable design provides a range of threshold rises from 1 in. to 6 in.
While this product is primarily used for doors that swing away from the house, they can also be used for sliding glass doors, doors that swing inward, and many other various entranceways.
Maximum ramp capacity: 300 lbs. for one axle and 600 lbs. for two axles.
Made in the United States and comes with a limited lifetime warranty.