... . G2.5. Two bearing alternator has a half-keytesting balance.TERMINAL AND TERMINAL BOX:The three-field alternator has leads brought out ... COUPLING:LYG senes alterators have two kinds construction.LYG senes Single-bearing. engine adaptor to SAE #OO,0 ,1/2 ,1 ... ,16,18 ,21LYG series doubl e-beanng. engine adaptor to SAE#OO ,0 ,1/2. 1,2 ,3. 4 ,5 Brushless synchronous generator