Blocking bullets and throwable objects using a "border"?

Im trying to create a border which will block any bullets or throwed objects (arrows, bullets, rockets, stones, tools etc).. I've already created a simple border which will block players or items (C#):

Code:

//creating the border
GameObject borderBig = GameObject.CreatePrimitive(PrimitiveType.Cube);//adding a collider
borderBig.AddComponent<BoxCollider>();//positioning and scaling the border
borderBig.transform.position = new Vector3(0, 0, 0);
borderBig.transform.localScale = new Vector3(10000, 1000, 2);

Do i need to apply a specific tag or layer? Or do i need to create something like an "entity-wall"?