Before revision: A barrier transfer machine, also known as zipper machine or road zipper, is a type of bus or heavy vehicle that is used to transfer concrete lane dividers, such as jersey barriers, which are used to relieve traffic congestion during rush hours.
After revision: A barrier transfer machine, also known as zipper machine or road zipper, is a type heavy vehicle that is used to transfer concrete lane dividers, such as jersey barriers, which are used to relieve traffic congestion during rush hours.