The 7668 Generac Parallel kit will pair two Generac Inverter generators that are between 3000-3500W to increase to the available output wattage. 
 
30-Amp (TT-30R) & 50-Amp* (14-50R) Receptacles
Excellent for RV applications small and large
Very easy installation. Kit attaches via, standard 3-Prong plug. 
Works with Generac IQ3500,Generac GP3000i, Generac GP3300i
1-year limited warranty
*Please note 240V operation in not available