Tank bottom cup on carburettor DELLORTO PHBG and others (small principal jet) not deep model

Tank bottom plate (anti-emulsion washer) to jet small step 5mm. Is placed between the needle jet and jet. Despite rumors is said of some, it is by no means a flange. Rather a piece that allows better mixing of the oil / gasoline (when he arrived in the tank), which prevents air bubbles and emulsions ... For DELLORTO carburettors PHBG, PHBG Racing Black / Red Edition Model ... not deep (also available in deep model).