Open Up and Say “Ahhhhhh.” Four our more experienced players, The Double Tunnel Plug features two plugs that slightly taper to the tip which makes it one of the most innovative butt plugs available on the market. Just like our Tunnel Plug, it also features the tunnel hole that goes all the way through the plug – clearing the way for various play including lube insertion, fingers, watersports and toys. And, the clear version also makes it possible to see right into the other person.