The CORP Diagonal Eyepiece Model 13 is a precision-engineered optical accessory designed specifically for DT series theodolites. Made in Japan with exacting standards, this diagonal eyepiece attachment offers enhanced viewing comfort and flexibility during surveying operations. The eyepiece features a robust construction with a secure mounting system that attaches via a simple clockwise turning mechanism. It comes complete with a protective carrying case featuring the CORP branding, ensuring safe storage and transport. The diagonal configuration allows for comfortable viewing angles when working in challenging positions or confined spaces, reducing neck strain during extended survey sessions. This professional-grade instrument accessory maintains the optical quality expected from while providing practical ergonomic benefits for field work. The included instruction manual provides clear, step-by-step guidance for proper attachment and use, ensuring optimal performance and longevity of the equipment.