I got to try out my new stroller with the double seat attachment. I went to my sister in laws for the day and we took the kiddos on a little walk at the park. It moves so smoothly even with both seats attached. This is the greatest invention ever. The stroller can be a single stroller or double. I can also attach the infant car seat and the second seat. The stroller is by Baby Jogger, it is called City select. It can go into 16 different positions. (I was able to get this luxurious stroller, thanks to my amazing staff at school that put together a stroller fund for the boys and I. Love them to pieces!)I would highly recommend the investment!