I have a couple of these. They work very well. Very sensitive to motion.
http://www.amazon.com/Stack-On-SPAL-300-Motion-Sensitive-Security/dp/B007J3E9PI/ref=sr_1_1?ie=UTF8&qid=1392695094&sr=8-1&keywords=gun+safe+light
http://www.amazon.com/Stack-On-SPAL-300-Motion-Sensitive-Security/dp/B007J3E9PI/ref=sr_1_1?ie=UTF8&qid=1392695094&sr=8-1&keywords=gun+safe+light