When you type fac into the console, what you are really saying is:

print(fac) 

The print function comes with different parameters, including the max.levels option

So you can specifically print fac without the levels by specifying:

print(fac, max.levels=0) 

This will give you the output you want.

As @jaySf pointed out in the comments of your question, you change the vector type from factor to character:

as.character(fac) 

Additional Info:

When you enter fac into the console, what you are really saying is:

print(fac) 

The print function comes with different parameters, including the max.levels option

So you can specifically print fac without the levels by specifying:

print(fac, max.levels=0) 

This will give you the output you want.