This is a 16mm Type II version. It was traded w/ Allister St. Claire a while back for another eyepiece. He indicated he thought it may be a NEAF item. I am not sure, but I have not found it to be different than a 9mm Nagler Type I or 12 mm Nagler Type II that I also own. I am selling it to fund another purchase, otherwise I would keep it. I can provide end-caps but no box. Shape is good w/ markings on both the 2" collar & 1 1/4" collar from set-screws.
Item sold as appears in photo below.
Paypal (+3%), Cashier's, MO or personal check accepted. Personal check must clear before shipping.