Have you ever needed a D20 roll to decide something but you didn't have one nearby? 

IF (and only if) you have already used a re-roll on a d20 in one our RTG RPG games, and things still aren't going your way, you may buy one of these and trust the scratcher gawds to have yer back.

Limit" 1 scratcher per already-failed d20 re-roll.