Have I struck vaccum check valve?

[mikeprather@xxxxxxx]

Hello all, yesterday I went looking for the brake 
booster vaccum check valve on my 72 Westy. Didn't appear 
to be one inside the engine compartment. While cheking 
the vaccum hoses underneath(gotta replace 'em), I 
discovered a loop in the hose just after it connected 
with the tube coming through the firewall. At the top of 
this loop was a little round black thingy that appeared 
to be plastic. Is this the vaccum check valve(Sure hope 
so, one less thing to buy)
thanks
Mike
72 Westy