SHCP=Secretaría de Hacienda y Crédito Público (Secretariat of Finance and Public Credit). The main function of the SHCP is to supervise, monitor and control the entry and exit of goods, and the ways in which they are transported.
This one is at the Ysleta-Zaragoza International Bridge between El Paso and Ciudad Juárez.
http://en.wikipedia.org/wiki/Ysleta%E2%80%93Zaragoza_International_Bridge