Watch List notes:

The Gus MacAmhlaigh Collection of Ireland - Part Four

Northern Bank Limited, £20, 20 October 1921 (1929), serial number A2137, Scott signature, large blue-black overprint on preceding issue, pinholes and faint graffiti, original paper, obverse nice and clean, though reverse more stained, fine and very scarce (only 5000 overprinted)
PMI NR 63, Pick 174 £500-£700