u.s.d.a prime grade highest quality grade of beef with the most abundant marbling u.s.d.a prime boneless sirloin steak grade u.s.d.a prime boneless kc strip steak grade sapp u.s.d.a prime grade beef filet mignon ооо u.s.d.a prime grade whole beef brisket u.s.d.a prime grade whole tri-tip gate_front