56cm seat tube length from BB center to top of seat lug. The "B" is the length of the fork steerer tube and is consistent with a 56cm frame. "W" means the frame was made at the PDG facility in Waterford, WI. J8810 means it was the 10th Paramount frame scheduled for production in September, 1988.
The 1988 stock 56cm Paramount frame has a 555mm top tube (c-t-c), 73° HTA, 75° STA, 70mm BB drop, 410mm chainstay length, 40mm fork rake, and 355mm fork height.