Knob treasury key
From A KoL Wiki
You might expect the Knob Treasury to be a little more security-minded than to use regular metal keys, right? Old vintagey ones too, not even pin-tumbler locks. Like, they should probably have computer-controlled locks and two-factor authentication by now. I guess, considering that they still use beans as money, the Knob Goblins are just too old-fashioned for that kind of thing. They probably think "cryptocurrency" is when you bury it in your grandpa's tomb.
Type: accessory
Cannot be traded or discarded
Quest Item+20% Pickpocket Chance
+50% Meat from Monsters
(In-game plural not known - currently impossible to determine.)