"Best Selling adjustable wheelchair ramps are perfect for home so wheelchair users can easily come and go in indoor or outdoor areas that need ramp assistance. Wheelchair users will also find them invaluable when visiting friends or family who may not have accessible entrances. Light and compact, these portable ramps are easy to travel with or store in the trunk of a car. Each ramp weighs only 6 pounds, making them easy to lift and position. They extend from 3 to 5 feet, for use on different step sizes and heights Each ramp can support 300 pounds (600 pounds total between them). How to Use Two ramps are included. To extend the ramps, pull sections one and two until the locking buttons are fully extended into the holes and snap into place. After use, simply retract them and put them away in their convenient nylon carrying bag. How to Measure for Wheelchair Ramps To calculate the length of the ramp you will need to measure the rise. The rise is the measurement between the ground and where the top of the ramp will be placed. The American with Disabilities Act (ADA) requires that public areas have wheelchair ramps with an incline of 4.8 degrees or less (a ratio of 1:12). This equals one foot of ramp for every inch of rise. For residential areas such as homes, ADA recommends a 2:12 slope. This equals one foot of ramp for every two inches of rise. To calculate the ramp length you will divide the rise by two. For home use, these ramps would work for rises up to 10 inches. Next, you need to measure the width of the wheels. These ramps have an inner track area of 4.5 inches. Be certain each wheel is no wider than 4 inches".