NAVIGATION
Potassium bromide crystal optic disc, 25mm x 2mm, polished both sides
Calcium fluoride crystal optic disc, 25mm x 2mm, polished both sides
Barium fluoride crystal optic disc, 25mm x 2mm, polished both sides
Sodium chloride crystal optic rectangle, 30mm x 15mm x 4mm, polished both sides
Potassium chloride crystal optic rectangle, 30mm x 15mm x 4mm, polished both sides
Potassium bromide crystal optic rectangle, 30mm x 15mm x 4mm, polished both sides