Identify weapon

How to identify what “BOX” was killed by “sword”

    void Update() {
            if (curHealth < 1) {
                    Destroy(gameObject);
            }
    }

if “box” have < 1 hp then Destroy.
I tried through:

    void OnCollisionEnter2D(Collision2D col) {
            if (col.collider.CompareTag("Weapon") && curHealth < 1) {
                    gm.points += coins;
            }
    }

But did not help.

Done.

void OnTriggerEnter2D(Collider2D col) {
	if (col.gameObject.CompareTag("Weapon") && curHealth < 2) {
		Destroy(gameObject);
		gm.points += coins;
	}
}