Quote:
Originally Posted by Smokentoke420  It depends, bu5 im pretty sure they use between a half inch and an inch and a half (cant remember the length, but it's either 1/2 inch, 1 inch, or 1 1/2 inches) and it's detectable for up to 90 days.
I'm not sure if they'd use more than the recomended length of hair to test back further or not.... shave your head? |
Idk man I've heard it's detectable for a lot longer then that but I could be misinformed.