You are bidding on a Leitz binocular viewing tube in excellent condition, as shown in the pictures. Both eyepiece ports are focusable so you will not need to use focusable eyepieces which are more expensive. Mating dovetail diameter 42mm for Leitz microscopes that use 160mm tubelegth objectives such as the Laborlux 11, 12, Dialux 20, 22, etc. If you have a question, I will try to answer it. Item being sold as-is, as-pictured.