All glass set of +1, +2 and +4 diopters. 77mm and labeled "Kalimar" and made in Japan. Comes in leather case and have been unused for 2 years. I purchased for use with a lens I no longer own and cost was about $100.00 for the set.
First $75.00 plus shipping takes the set 
Many photos taken at www.pbase.com/dhaas were shot with the +4 (White sharks mostly.)
Email: davidhaas@sbcglobal.net
or call 330-678-0591 or 330-329-5981 (cell) Eastern time zone
