Comparison : Item # 0002A-67, NaCl Polished Disc- 25mmx4mm
Item # 0002B-136, KCl Polished Disc- 25mmx4mm
Item # 0002C-74, KBr Polished Disc- 25mmx4mm
Item # 0002D-181, CaF2 Polished Disc- 25mmx4mm
Item # 0002E-176, BaF2 Polished Disc- 25mmx4mm