This Inline Chain Tensioner for roller chain is perfect to adjust the desired tension in a long run of chain on mechanisms such as elevators and arms. This is ideal where there is at least a ~3 in. section of chain that never passes over a sprocket in a given mechanism. Pair these with either two #25 Master Links or two #35 Master Links depending on your chain size and integrate this to your robot for an easy-to-use chain tension solution!