formula 420 is basically fancy, overpriced cleaner mix... they sell it at basically every headshop... it comes in a white container that says "formula 420" real big on it... it is actually a bluish liquid with some salt like (well i think it actually is salt) crystals in it... when you put it into a piece, you shake it around real good, and the crystals don't melt in the liquid so the little crystals gently scrape all the oils and resin off of the inside of the glass... dont' get me wrong formula 420 works great and leaves your pieces smelling real nice and clean... but it isn't worth 8 bucks... like i said it is like salt and rubbing alcohol with some other ingredients and blue food coloring.... try the salt and rubbing alcohol and then if your bowl still ain't clean... go buy some 420... but i think you'll be pretty damn satisfied... just tryin ta help a fellow stoner out... good smokin