that model for many many product for cnc and 3d printer
STl is for medal
obj low in z for jewellry pendant and decoration
obj 2 for pendant and decoration
FBX : to open and ediet it easily in any version of 3ds max
ZTL : to open and ediet it easily in any version of ZBRUSH -open
if you need any ediet or ask any question please ask me :)