Four Paws Freestanding Walkover Pet Gate. These 17-inch high pet gates are tall enough to keep small dogs in designated areas, but easy for people to step over.
Find the pet gate here: https://amzn.to/2NTLOKW
It has been successful in keeping 2 small dogs - a pug and a chihuahua mix from entering "off-limits" places.
This wood gate from Four Paws safely secures pets without creating inconvenient barriers for people. It has 3 hinged panels; sets up quickly to barricade and folds quickly for removal and storage . No tools or assembly are required