A connector assembly (100) includes a first connector (10) and a mating second connector (30). Each connector includes a number of leadframes (21, 41) stacked one by one. Each leadframe has a first leadframe housing (211, 411) and a second leadframe housing (214, 414) attached to the first leadframe housing. Each connector includes an array of first terminals (5) and an array of second terminals (6) respectively mounted along the second and the first leadframe housings, and a pair of latching members (25, 45) mounted at opposite sides of the leadframes together with the first and second terminals to tie the plurality of stacked leadframes as a whole.