

AEA Zeus MKII fill port plugged
I need some help, please. I just ordered this Zeus MKII from AirgunTactical.com and I spotted what might be the trigger return spring hanging down from the trigger group (see photos). But before going to replace it, I figured it’d be best to bleed all the air out. It arrived full so I looked at the foster fitting and it has this weird brass filling stuffed in it effectively blocking the port so that I cannot degas it. Does anyone know what this brass filling is and how I should proceed? And can anyone confirm what spring that is hanging out?
Thanks!