Free Shipping For Properties Product

Hello everyone,



I need same like buy together action but;



So let says i have A,B,C products and i want add table bellow X1,X2,X3 products



What i want?



A products page show X1,X2,X3 products . Customer add A products to basket and add any X product to basket than shipping get free.



I make this than get X any product buy only get this X products free shipping, X products only buy add shipping but any A,B,C product with X products buy than get free shipping.



I USE 306



Anyboy have a idea?