... The versatile and efficient INVERTOSCOPE? combines the highest optical performance with unsurpassed mechanical quality, and is backed by LOMO's unique lifetime warranty, the most comprehensive in the industry. ... A 15X focusing eyepiece with two interchangeable reticles (a 10mm/100div scale and a 10mm x 10mm/400sq grid) for convenient measuring and counting. ... A set of stage inserts and extension plates to accommodate a variety of sample vessels such as Petri dishes, flasks, microtest plates, etc...