Can someone help identify this first stage?

[Roberg.Willian]

I just started going through some old gear of mine and found this first stage laying around, must have been store here since 2008/2007, can you guys help identify what brand is it? Thinking if its worth sending in for service and see how its working, don't remember why I stopped using this, serial number on it is 501627.

One of the LP ports is actually bigger than the others, I think 5/16 or something like that

 

[Centrals]

Apeks DST.
The larger LP port(1/2") has been replaced in newer model.

 

[lowwall]

It's a 1/2 inch port. You can get an adapter that screws into the port if you don't want to bother with keeping separate hoses for it.

 

[Roberg.Willian]

thank you folks for the response, I'm going to send it for service and put it back to good use. Appreciate it!!

 

[Centrals]

If you have the service kit then it is NOT that difficult to do it yourself. There is NO special tool required, unless you regard the C-spanner as special.
Youtube should have videos on the subject.

 

[buddhasummer]

thank you folks for the response, I'm going to send it for service and put it back to good use. Appreciate it!!

As @Centrals has said, dry simple to do yourself. If that is something you'd be interested in, not everyone's cup of tea, happy to help with service manual, schematics, kits and advice. Feel free to DM me if it appeals