is a letter. X identifies any independent telephone company location. The letter otherwise is the location type: B (international boundary crossing), E (end point or non-international boundary), J (junction), M (manhole), P (pole), Q (radio location), R (repeater), S (toll station) or U (other or utility ()). The eighth through eleventh characters contain a four-digit identifying number. The code for a communications satellite is STLT (satellite) EO (earth orbit) Q (radio location) then a four-digit identifier. Customer Site Code A Customer Site code is used to uniquely identify customer locations. These locations are required to identify customers, circuit terminations, facilities, or equipment for each specific customer for facility provisioning or other requirements. This format contains 6 characters representing location and a 5-character Customer Site Code element. The first six characters are the city (four letters) and province/state (two letters) The seventh character is a number, followed by a letter, then three more numbers. Entities within client-owned buildings (such as Centrex installations) are coded in the same format as telephone company buildings. Examples HSTNTXMOCG0 HSTN = Houston TX = Texas MO = The AT&T telephone exchange office at 4068 Bellaire Boulevard in West University Place, Texas—the office is known as the "Mohawk office" CG0 = The first (or perhaps only) electronic telephone switch at that location (in this instance, analog - now HSTNTXMODS0 as a digital switch) This code shows two characteristics: Telephone companies often give names to their central offices. The names frequently relate to the name given to the exchanges served from that office in the days of two-letter, five-number dialing, where a telephone number might have been referred to as "MOhawk 3-1234". The numbers are now listed as all-figures, so (713) MOhawk x-xxxx becomes +1-713-66x-xxxx. The Geographical code field does not always align exactly with the city location. West University Place is an enclave of Houston, Texas. PTLDOR12DS0 PTLD = Portland OR = Oregon 12 = The CenturyLink "Atlantic office" at 2911 NE 24th Ave DS0 = The first (and perhaps only) digital telephone switch at that location. While some telcos use -CG suffixes for both computer-controlled analogue and full-digital electronic switching systems, -DS is always a fully digital switch. Some telephone companies named their central offices, but did not reflect this name in the CLLI code, as in the above example with a numeric location code. PTLEORTEDS0 PTLE = Portland OR = Oregon TE = A specific