T-note

a "T-note", a shorthand for "Treasure note" or "Promissory Note" is a form of currency in vogue among British Professionals when actual money is short.

Each T-note is basically a promise of one's choice over the entire treasure haul from a lair. You can theoretically redeem the note by asking the note issuer to run a lair, as indicated, and you get first pick of the various pieces of gear found inside.

T-notes are labelled with "amount, T, level". The initial number is the size of the lair, ranging from 1 (single-guardian lairs) to 9 (the largest lairs ever found thus far). T is a stand-in for Treasure, referring to the treasure boxes within, and the last value is the average level of the lair (usually within 5%). The worth is usually consistently higher than the average selling price of average gear at the given level, since one can always hope to win big on a run.

Example: a 4T200 note is worth first pick on a 4-guardian lair at level 200, plus or minus 5% (190 to 210).

T-notes are worth based the reputation of the issuer, his or her team, and usually backed by the Company employing them. A T-note from Princess Charlotte is worth far more, all things considered, than a note issued by an unknown team.