"Silver Spring portable aluminum threshold ramps provide easy access over doorway thresholds, single stairs or steps and short rises. Great for power chairs, wheelchairs, mobility scooters, and foot traffic with shoes. The specialized EZ-Traction double ribbed plate surface is designed for superior grip with power wheelchair or mobility scooter wheels in all weather conditions. Each threshold ramp measures 16"" x 36"" to fit standard home doorways and weighs 8 lbs for lightweight carrying."