Bakerhill is right, that's the IPC board.
If you want to do yourself a favor, remove it. They're pieces of junk, and cause more problems than they fix. You're actually MORE likely to have issues with it than without it, as those legs really like to loosen up where they are soldered to the board, and your deflection system stands a good chance of frying when that happens. I've seen it on many deflection boards. I always remove them on all 6100 boardsets that I refurb.
To remove it, just desolder all of the legs, pull it off, and then replace the following four resistors:
- R600 and R700 (1.2k 1/4W)
- R606 (4.7k 1/2W)
- R706 (2.2k, 1/2W)
The result will be many fewer points of possible failure, and a more reliable board.