add_action( 'do_meta_boxes', 'feature_image_box' );
function feature_image_box( $post_type ) {
	global $wp_meta_boxes;
	if ( ! current_theme_supports( 'post-thumbnails', $post_type ) || ! post_type_supports( $post_type, 'thumbnail' ) ){
		return;
	} else {
		foreach ( $wp_meta_boxes[ $post_type ] as $context => $priorities ){
			foreach ( $priorities as $priority => $meta_boxes ){
				foreach ( $meta_boxes as $id => $box ){
					if ( 'postimagediv' == $id ){
						$wp_meta_boxes[ $post_type ][ $context ][ $priority ][ $id ]['title'] .= ' 1920w x 700h';
					}
					remove_action( 'do_meta_boxes', 'feature_image_box' );
				}
			}
		}
	}
}