a $50 bag of weed, for the rich or elite potheads.
(JFK is the president on the 50 cent piece.)
...50 cent the Half Dollar, not rapper you idiot.
Equivalencies (hurts to do this but I know someone is confused):
5 Dime bags = 1 JFK bag
10 Nikel bags = 1 JFK bag
Dealer: Hello citizen, what can I get for you today? Nickel bag? Dime Bag?
L33T Smoker: Fuck that, hook me up with a JFK bag.
Dealer: That will be $50 kind sir, would you like paper or plastic?