Aluminum Spigot Truss as the name implies refers to its connection using the pin card tight way, two truss between the installation of the connecting axis of the large hole facing out, the small hole facing in. Insert the pin into the mouth with a hammer to tighten, so that the two truss are connected very closely, this connection is fast, it is very high security, even more than the screws to screw are high, so many customers choose this spigot truss.