Can’t figure out what this is on down tube

Received my Endurace CF7 today and while putting it together I noticed this hole on the down tube between the bottle cage screws, with a clip in it. I tried to take it out to see what it is but there’s something zip tied to it. Thought maybe it’s where the battery is since I have a Di2 group set but I don’t think that’d make sense for the down tube. Anyone know what it is and can help me out here? I looked through the manual but didn’t find anything helpful. TIA!