The Castroviejo Caliper Screw Mechanism Straight (20 mm) is a precision ophthalmic measuring instrument used to accurately measure distances during eye and microsurgical procedures. The 20 mm scale allows reliable measurement for surgical planning and execution. Equipped with a smooth screw lock mechanism, this caliper maintains stable positioning once adjusted, preventing measurement errors. The straight tip design improves visibility and control, making it suitable for delicate ophthalmological applications. Manufactured from medical-grade stainless steel, the instrument is durable, corrosion-resistant, and fully autoclavable, meeting hospital sterilization standards.