GNC Jet Agitator -  1/2" NPT (F)- 3/4" NPT (M) Out Poly  HY-3371
Typical uses by color
Green - 5/16 Orifice Diameter -  Diaphragm Pumps such as Kappa43, AR30
Red - 1/4" Orifice Diameter - Piston Pumps such as the P530
Black - 3/16" Orifice Diameter -  Medium pressure pumps 
Yellow - 5/32" Orifice Diameter - Smaller Diaphragm pumps such as Remco 5500, Remco Fatboy, Shurflo
If you also need the fittings between the agitator and the spin-weld fitting on the tank, order 1 each of:
FT-3RB3412 and FT-3M12