I'm with Bill on this.

You got a 2 slot SmartJack housing with two T1 cards installed.

THis is what I found out about the cards with a quick goggle search.

Quote
This Remote Unit HRU-402 functions as the remote ends of repeaterless T1 transmission system


Patrick T. Caezza
Santa Paula, CA 93060
C-7 - Low Voltage System Contractor - Lic# 992448