DEFINITELY remove the filter and throw in some cardboard (like you would for a normal joint). The good stuff will stick to the filter more than anything else.

"...the cigarette filter also performed worse than the unfiltered joint, by about 30%. Researchers speculate this is because cannabinoids are exceptionally sticky and adhere to other solids. Hence, any filtration system that picks up particulates is likely also to screen out cannabinoids."

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