The Unico M251 Monocular Microscope is designed for College Level Instruction and Discovery. The versatile M250 Series offers your choice of Halogen or LED Illuminated Models. Warranty: 5 Year Limited Warranty (1 Year Electrical System Warranty; excludes Bulbs & Fuses). The M250 Series Microscopes have been recently updated with the Reverse Nosepiece, Larger Base and Sturdier Body Construction adding more value for your money. Your choice of Monocular, Dual-view, or Seidentopf Binocular Heads in corded or cordless models. All heads rotate 360ç. Binocular Heads have Diopter Control on One Eye-Tube and Interpupillary Distance Adjustment Settings (55-75mm). Standard M250 Series features include Color Coded DIN Achromatic 4, 10, 40 and 100x Objectives and 10x Widefield Eyepieces. Objectives are mounted on a 4-position, positive click-stop Reverse Nosepiece. All optical surfaces are precisely polished, sealed and coated with anti-fungal, color correction and hardening agents to improve true color viewing while increasing the lifetime of the lenses. Unico M251 Monocular Microscope Size & Weight: Size: 8.5in x 6.5in x 14.4in. Weight: 13lbs (6kg). Shipping Size: 12.5in x 8.5in x 16.5in. Shipping Weight: 13lbs (6kg). Unico M251 Monocular Microscope Specifications: Illumination: M251: Halogen (6V, 20W). M251LED: LED. Head: Monocular. Eyepiece: 10x WF. Objectives: 4x, 10x, 40x, 100x. Condenser: NA 1.25. Diaphragm: Iris. Stage: Mechanical. Focusing: Coaxial. Unico M251 Monocular Microscope Literature: Unico Basic Laboratory Microscopes Brochure Unico M250 & M280 Basic Lab Microscopes Brochure