Erecting Post with Pass-Thru both styles are available at 39" or 45" high. Perimeter's Erecting Posts with D-Ring are used to build and support a horizontal lifeline during the steel erection phase. When centered between two Erecting Posts with D-Rings, our Erecting Post with Pass-Thru provides the ability for movement between bays without ever disconnecting from the lifeline. This post provides a 100% tie-off point during the building erection phase. It's innovative design eliminates the need to disconnect from a lifeline, but allows it to pass through the top of the post to easily relocate.