If it's a foam model... the Chinese refer to PA glue as the clear to yellowly, sticky, tube stuff they often supply with foam models in a tube. It's light, but longer drying times make it somewhat more difficult to work with. (GWS supplies it with almost model they sell)

It kinda looks and applies like the plastic model cement but is not, as it's foam safe.

I usually use epoxy sparingly in the areas they designate PU glue for... (usually fuse assembly, wing joining, etc)

If this ISN'T a foam model... then what is the application is is calling for? what two components are being glued?

Then we can help you select what glue will best serve...