Pipe/Pole restraints

Put two tags on post #3339918 for the type of restraint depicted. While pole_restraints is a more accurate description, Internet searches for terms along the lines of pipe_bondage are what actually bring up relevant examples.

The post in question may currently be the only example here however, as searches for pipes and restrained for example only find subjects restrained to pipes, rather than by the pipes themselves.

Wouldn't this just be a variant on a spreader_bar?

Not at all. A spreader bar simply keeps the legs spread. The concept this tag is for is the use of poles/pipes as a restraint. A particular part of the appeal is that because the restraints are built around the subject, it allows for all manner of unique and awkward positions.

As there isn't a tag for it already AFAIK, it's hard to tell if there are currently any other images it applies to, and it might be a bit niche at present. For reference, here are some photographic examples:

https://i.pinimg.com/originals/9d/20/6b/9d206bbac558a3eb1b0922bd5c2c2235.jpg
https://cdn4.images.motherlessmedia.com/images/039F69B.jpg?fs=opencloud
https://ftopx.com/large/201403/92342.jpg