Please help me identify what this part is that is found on a 2006 Honda CRV (2.4L iVTEC)?

Question

Dear Expert,

I am trying to access the VTC filter to either clean or replace it as a first step to address two codes: P1009 and P1078. In the process of removing the power steering pump and autotensioner pulley to access the VTC filter, I discovered that I could not remove one of bolts on the autotensioner pulley because there is a part that is obstructing my ability to get in that area. I don't know what the part is or what it does, and I have not been able to locate it on any web site so far. Can anyone tell me what the component is, and how to safely remove it?

I have tweeted a picture to describe what I am talking about:

https://twitter.com/dgc001/status/1039220103815077888

Thank you.