PVC plumbing, which cement to use??

[Foogoo]

I've got to plumb a skimmer that's mostly PVC with one grey fitting which I'm having a heck of a time trying to identify as ABS, polypropylene, grey PVC, or whatever. Is there a 'universal' cement that would be safe to bond PVC with most other plastics?

 

[BeanAnimal]

If in doubt you should use the ABS/PVC glue instead of the PVC glue.