[jod7888]

I'm wanting to use a single beam of 16 feet (thinking a 4x4) in length resting on top of 4x4's on either end buried in concrete and using a simpson connector of sorts a the top. This will be sort of a monkey bar type setup, but using ninja type rings instead of bars. Is this going to be sufficient? If not, how about a single 2x8 or 2x10 on end? I'm going super simple with this but want it to be sound.