These are a pair of brand new 16X wide field microscope eyepieces.
They are Achromatic (International DIN/JIS) standard size with outside diameter of approx. 23mm.
Model Number EP16X23-V299; The eyepieces will provide crisp images across a wide field of view and will fit most standard size microscopes.
Professional and practical design with beautiful appearance, easy to carry and use.
Usually used in laboratories, schools, teachers, sample observation, eyepiece protection, etc.