The Traffic Barrier-Transfer Machine Caltrans is studying the durability and performance of its Barrier-Transfer Machines, also known as “zippers.” Facebook Prev Article Next Article Engineering Checkout these cool gadgets... Related Posts The Truth About Pumped Hydro 3D Printed Objects that are Otherwise “Unmanufacturable” Super Fast Cameras (1 trillion FPS) Futuristic TriFan 600 Can Take Off Vertically Like a Helicopter 1773 Mechanical Devices Were Amazing How a Tugboat Works