Vernonscope 32 mm Brandon eyepiece , 1.25". Four element designs give a flat, beautifully corrected view. Optical elements are exactingly ground and hard-coated with magnesium fluoride. Made in USA. The 32mm Brandon eyepiece has about 26mm eye relief.  The apparent field of view (AFOV) is about 45 degrees.  It weighs 3.1 oz (88 grams.)