Saw these small strobe lights (11mm x 13mm ) and thought I'd try them. The 5 I bought didn't make it past my co-workers, so we just ordered more. They flash blue and red and have a removeable magnetic base. They are bright in a closed room. They are 5 strobes for $5.00, including a spare set of batteries. Can be seen at www.countycomm.com in the flashlight section, Tiny LED strobe.These guys are getting my money every week !!!