Differential breather valve? I think I'm missing something

[CrazyInteg]

I bought a used differential for my car and on the top there's this nipple with nothing connected to it. A quick look through some tech articles mentions a breather valve.

What connects to this nipple of the differential? Is there a rubber hose on the 240 that plugs into the differential? Do I need to buy a part from Nissan/NAPA?

I'm just waiting for spring time so I can take my baby out of storage!

If it matters: 1991 240sx, currently has VLSD with 4.08, swapping in a Skyline 4.44 rear end. Both differentials have the star shaped axels (5 bolt?)

[CrazyInteg]

I just went to go look at it again, and I was incorrect in my description. There is no nipple. Here are some photos.

[Hijacker]

Looks like it's been broken off at some point. The breather doesn't connect to anything, it just has a small little filter like cap on the nipple to allow air to move out but not let fluid slosh out.

Also moved to 240 tech

[94_240sx]

I replaced mine and it was like $7 from the dealership. Yeah, it's broken off for sure. Just use flat head screw driver to pop it out.