i just got the trius one step, there is no tension on the arm when you load it and when you put your left foot on the cocking lever it pulls the arm back and releases it. it works great. I have a hoppes #9 mounted to a spare tire as well, it is released by a string but it jumps around quite a bit when you release it. A few of us have gotten our fingers smashed by the throwing arm when it hasn''t catched proper when you #### it. the trius is way better because you are standind on it so it does't jump around when it releases. both throw singles out to about sixty yards but they don't like coldwell industry clays as the are softer and most explode on take off. the ones from ct are harder but sometimes you can hit them, they will not break, but you will find six or more pellet holes in the lid. I got the trius for 180 bucks just last month