Davis Echomaster Radar Reflector 
Echomaster™ Radar Reflector
Give ships a chance to see you in fog and low visibility. This model provides 12 square meters of radar cross section. Ranked on of the best radar reflectors and rated superior by SRI after the most rigorous tests ever conducted on radar reflectors - some costing 10 times as much.
All our Echomaster models can be stored flat and assembled in minutes. The plates are made of sturdy, stamped 0.05 in. (1.3 mm) thick aluminum with riveted nylon corner latches for quick assembly or disassembly. Install around a backstay or make your own hanging bridle as described in the 16-page Radar Reflector Booklet included with Echomaster.
Owner's Manual (pdf)