The RAM-PF-585-18 is a 18" flexible metal pipe, with composite cover, that has a 1/4" NPSM male thread at both ends of the pipe. 

NPT / NPSM Thread Statement: 
There will be some binding of the threads due to the nature of the NPT / NPSM threads. The mount will be secure when tightened as fully as possible.

Material: 
Metal with Composite Cover

Note: 
Part number reflects product packaged in clear clam shell for store shelf display.