Also known as a cable protector, cable ramp, and Yellow Jacket, BumbleBee, Guard-Dog, (all brand names). Placed wherever portable cable or wire must run on the ground in a traffic path. Most have five channels, which conveniently matches five-wire, 4/0 feeder. The jigsaw/dogbone shapes allow multiple units to interlock together end-to-end. Note: Different brands are very, very, rarely compatible with each other. http://www.checkersindustrial.com/products/cable-protectors/yellow-jacket/ Note that at least one company is making them with their own internal lighting: http://www.fireflycableprotector.com/ .