Professional Nd:YAG laser rod, 5 mm dia. x 60 mm length, flat - flat ends, made in Turnov, Czech Republic, by the famous crystal growing company Crytur, in 80's (pictures #1, #2). Very good optical quality (see transmission, picture #3), slightly used in an R&D laser, no original box. Ends are AR coated. The yellow color is due to additional doping with cerium oxide (CeO₂) to reduce solarization (i.e., absorbing color centers induced by the UV light of the lamp) during pumping - this assures a longer lifetime of the yellow rod than that of a regular violet Nd:YAG rod, under the same pumping conditions. Ends flatness lambda/10, ends parallelism less than 10 arcsec, front surfaces less than 5 arcmin from rod axis. Can be used as a relatively high energy multimode oscillator, or as an amplifier of a smaller, 3 mm dia. oscillator. Best to be pumped with a flashlamp with matching discharge size (4 - 5) mm dia. x (50 - 60) mm length. Good for material processing, medical, research, or educational lasers.