Please refer to the manual that comes with your kit for specific installation instructions. The slope determines the speed of the zip line. Essentially this is the angle you set the cable at between the two trees. The slope is calculated by multiplying the distance between your trees times .03 or 3%. More details on Slope can be found in the Zip Line Gear handbook included with your purchase. You can also view a digital version of the “Cable Slope & Sag” right here. We recommend finding a landscape with a natural slope of 3% to 6%, This is a 3’ - 6’ foot drop per 100’ feet.  For zip lines that will NOT utilize a Bungee Brake System, (a Stop Block is NOT a braking system) the maximum allowable slope is 3%. For zip line setups that include a Bungee Brake, the maximum allowable slope is 6%.  !!WARNING!! Zip line must never exceed 6% (6’ foot drop per 100’ feet) riding slope. High speed collision with end point may cause injury or death.