If anyone has the military SDU-5E distress marker light/strobe light and has been frustrated by the cost and availability of the batteries, I was recently made aware of a company that makes an adaptor allowing for the use of lithium CR123 batteries for a little over $9.00 plus shipping. I left the web site at home so I will have to wait untill tomorrow before posting it here. Before thinking things through, I bought a couple for my strobes. However, I started to look at the photo of the adapter on the web site and said to myself they look like the end of the battery itself. I took one of my old batteries, pulled the cap off the dry cell portion, and curled a 4-inch piece of stainless steel wire around a thick pencil, to make a spring. Popped a CR123 battery in the compartment, added the spring, screwed on the cap on and low and behold the light worked fine. You just have to make sure to bend the end of the wire so it makes contact with the + terminal. I wish I tried this before buying the adaptors, but oh well. I am not sure how long the strobe will flash on the CR123 batteries in comparison to the correct battery, but his is a great alternative. Also there is someone on Ebay selling the strobe with the adaptor for $ 22.50 plus $4.50 shipping.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=748865778. Pete