This model is a Torii (Shinto Gate - Hollow) tsurikawa!
This tsurikawa is 10.5cm wide, 9.7cm tall and is 1cm thick.
Tsurikawas are designed to work with a 1 inch (25mm) nylon strap, 2x M4x10 screws and nuts, and a 3D printed strap lock (the models for the strap locks are available free - check out my other designs!)
The images show the final product - an assembled tsurikawa!