If you are the type of person that just can not get enough of a good thing, then the Sativa Protab Refill Pack is for you. Each Refill Pack contains 40 tablets, and each swallowable tablet contains 25 mg of THC and takes effect in 30-90 minutes, with a duration of 2-4 hours. Should you want to consume a lighter dose, they are scored so you can easily split one in half.