Is your standard mouth tip not quite doing it for you, or do you need a spare? You've come to the right place. Stock up on wide, medium and narrow bore mouth tips to fit the S17 and S22 Topfill tanks. Please note, these mouth tips also double up as topfill caps, and are not compatible with the original S17 and S22 bottom fill tanks. Our S22 TF tank ships with the wide mouth tip as standard. Our S17 TF tank ships with the medium mouth tip as standard. The narrow mouth tip is a great choice if you're looking to restrict down your airflow even further.