East Denver Eruv

LECHI

A lechi is a "strip" or pole of some variety used to represent a doorpost. This can be made of anything solid -- from rope to a 2x4 or I-beam. With the East Denver Eruv, lechis are most often made of plastic U-guard, which is most commonly used by telephone companies for protecting the grounding wires rising up a utility pole. The lechi is typically attached to a utility pole starting at the ground and rising upwards to just beneath whichever cable is being used as the vertical member of the zurat ha'pesach. 

Tzurat ha'Pesach

A tzurat ha'pesach vaguely resembles a doorway, consisting of two sideposts and a lintel that passes over them, which are the basic components of a doorway. According to halacha, a tzurat ha'pesach is considered a bona fide enclosure. Thus, if all gaps between the existing "walls" are "closed" with tzurat ha'pesach, the area is regarded as fully enclosed. (Text modified from here.)