U clasp classic, Allen screw

this is a U clasp, with Allen screw, technically the screw doesn't visible when it close, you have to use Allen ranch for opening and closing the screw.  overall size is: 30mm x 39 mm screw length is 30 mm. minimum thickness is 1 mm so I don't suggest rescaling it. the gap is .1 mm this design is suitable for gold, silver, steel, bronze, and so on.  let me know if you need any specific size.