There is no "rod" involved.
They (Spartan) sell a picatinny adapter, a smal item that mounts to the pic rail and the bi-pod attaches to that. I really like this bi-pod for it attaches and removes in seconds, this is great for 80% of the time I don't need one so no reason to have it installed all the time and when I do it is silly fast to install. It is held on by a powerful earth magnet, it is a brilliant concept. The bi-pod weighs ounces so a breeze to carry in a belt holster (optional). I also have a "Redkettle" brand sling that has a "Javelin" specific holster built in so it is always within reach.
Tim