Products 05/04/2011 Trailer-Mounted Work Lamp: Adjustable Height The Magnalight HIDTH-66X2-70W is a trailer-hitch-mounted work light. It boasts a 12,600-lumen floodlight that can illuminate a 600-ft by 575-ft work area. It has two 70-watt HID lamps and a 3-ft to 8-ft adjustable height. It connects to a standard trailer hitch with a push bolt and slide pin. A thumb bolt at the base of the mount can be loosened to swivel the lamp 180�. The HID lamps are waterproof and can be used in rough working conditions. The work light can run on 12-volt or 24-volt DC power. Larson Electronics; 800-369-6671;
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.