This model is a supportless, print-in-place tensegrity structure. Like many others, it utilizes “bridging” to make the strings. 

"Tensegrity is a structural concept that achieves stability through the balance of tension and compression forces. In tensegrity structures, components, such as rods or struts, are connected by a network of tensioned cables. Unlike traditional structures, where elements are directly linked, tensegrity relies on the dynamic equilibrium created by the interplay of pushing and pulling forces. This unique design results in lightweight and resilient structures, finding applications in fields like architecture, biology, and art."

If you're printing with the raw file, make sure to use a 0.4 mm nozzle and a 0.16mm layer height for the bridges to come out clean

Enjoy : )