4 stars for the alarm, but I would frankly give the 12 gauge blanks only one star, as I have found that about one third of them are pure duds. I have enclosed pictures of 3 consecutive shots and all 3 have dented primer caps, yet only 2 of them actually fired. The alarm knobs were tight. Also, maybe a stronger pull ring on top of the alarm would be beneficial, to earn the 5th star for the alarm itself. Nice perimeter alarm, but poor grade blanks. As a former combat paratrooper/medic, I would absolutely not trust these blanks to alert me or my men in times of danger, inherent or expressed. Please respond.