We offer custom prenta prisms, which are generally used in optical tools such as collimation, ranging, measurement and other instruments. The pentagonal prism deflects light by 90 degrees through two reflections, thereby causing the image to deflect and stand upright. Since the 90-degree deflection angle is not affected by the direction of the prism, slight movement of the prism position has no effect on the accuracy of the 90-degree reflection deflection of the reflected light and can be used in places where the prism cannot be accurately positioned. It can also shorten the optical path of the instrument.