A peace of foil u put over ur left pointer finger. Used to cover the finger, resulting in not burning your finger. Used when taking res hits from a bowl or a glass pipe. The finger is placed over the "carb" while lighting the center of the bowl.
Yo go get me the foil finger foil thimble so we can take some hit from this empty bowl.
o we outta weed? Damn, I got that foil finger coming right up!