Can you?

[Annie&Amy]

Use a under rug on it's own without a stable rug on top? xxx

 

[mpicton]

I can see slight problems arising by the fact that wee and all wet stuff would be easily absorbed as there's nothing to stop it. If it was my messy boy the whole under rug would be soaked by the morning!

 

[Sarah_Jane]

Often underrugs have less securing straps so you may need an addition surcingle or similiar to ensure it is secure if using as a top rug.

 

[samsaccount]

As long as you add a surcingle to it so that it is secure i see no problem with just using the under rug...(apart from the obvious....it becoming a mess when the horse lays down).