The ATUD and TUD expanding take-up devices are suitable for rod diameters from 1/2" up to 2" and shrinkage up to 3". Expanding screw-style take-up devices provide the lowest device displacements. For installation, ensure that the activation pin is pointing up and facing toward the inside of the building space. The pin can be pulled anytime after the nut has been tightened onto the top bearing plate and must be pulled by the time the building is fully loaded. Shrinkwrap should remain on the device until the pin is ready to be pulled. Before activating an ATUD make sure the pin on the take-up device on the floor below has been pulled.