Technical features:
* Item : 500KS, 500KR, 500KL, 500KXL
* Power: 5.0X
* Working distance: 340mm(S),420mm(R),500mm(L),550mm(XL)
* Depth of view: 35mm (S); 35mm (R); 35mm (L); 35mm(XL)
* Field of View: 40mm (S); 45mm (R); 50mm (L); 60mm(XL)
* Weight: 84g
* Frames: Ni-alloy or Titanium