KILLER LABZ Stim Reaper is a very effective Pre-Workout. One of the strongest pre-workouts out there. Assess tolerance by consuming half of a scoop in 4-6 ounces of water 30 minutes pre workout. After assessing tolerance consume 1 full scoop in 8-10 ounces of water 30 mins pre workout. Do not exceed more than 1 full serving per day.