How to tighten single hole kitchen faucet?

[Kris]

My kitchen faucet (single hole) is loose and I can't figure out how to tighten it or what tool I would need to use. I tried looking online, but this method of attachment doesn't seem typical? Does anyone have any tips? Photo of the faucet parts from underneath are attached. Thanks!

 

[Geofd]

cant tell what those black caps are but it looks like there are two threaded rods sticking down if so there should be nuts to tighten against those flat peices