Or underbed straps with D-rings to which you can tie ropes or clip to.
My problem with any underbed system is twofold. Adjusting and accessing them is one. They never "stay in place" between sessions and I like spontenaity when I start in with bed bondage.
The second is even "worse" because under-the-bed systems though great for tying someone down, isn't very adaptable to tying four limbs to two corners or tying someone into a kneeling position or tying someone to the top of the headboard, etc. etc.
In otherwords, I'd go search for something with bed posts, tall bed posts, at all four corners. With attached rings or some other way to secure restraints near the top of the post without necessarily slipping down to bed-level.
