Paw Essentials Light Four Wheel Pet Carrier Stroller Cart for Cats and Dogs - Pink, up to 22lbs

The best thing is that it is compact and easy to transport. It works best if the top is zippered shut. If you don't enclose the dog, there is no real front support. Since my dog is 20 lbs, it's a tight fit. Much better for a dog 15 lbs and under.