need help identifying this drain plug

[tshih]

Hi,

almost finish draining the tiptronic S in wife's 1996 993. Wondering what that drain plug in the upper right corner of the differential leads to (more ATF or hypoid gear oil?). Haven't quite figured out where the refill plug is. If more ATF then is that region 's oil filled through the quickfill hose at the tiptronic fill point?

Hope photo uploaded.

Tom