Andersp: such 'holes' are customary and work like with the Bunsen-Burner,
they decrease gas consumption by adding some air to a gas/air mix - you will get
a rather mellow flame without them, or the straight blast with some extra air soaked ... ~*~
(hide) If you want to find out more about some games you can check the links section and see if you find any interesting links there. (pauloaguia) (show all tips)