PWA 58159 and 58163 are molding numbers , the actual part numbers are 47603-TDM ( Large board with 3 rows of ports and one white clip) and 47603-C5 ( narrow board with 6 black ports and 6 white clips). The 47603-TDM is a phone distripution board. You terminate your incoming service line on the white clip labled "From Demarcation" to provide signal to the board. Up to 4 incoming phone lines can be used, each port has a number sequence under it telling you which of the 4 lines are available on that port.
The 47603-C5 board is a board for landing your cables on that come from throughout the house. You can then make connection to these wires using the ports on the board. Each port connects to one white clip, they are not bridges meaning that you can not just make one connection and provide signal to the entire board.