P 2925 (OTTO) Praseodymium(III) fluoride, anhydrous, 99.9995% Cas 13709-46-1 - used in the motion picture industry for studio lighting and projector lights. P 2925 (OTTO) Praseodymium(III) fluoride, anhydrous, 99.9995% Cas 13709-46-1 - used as a single mode fiber optical amplifier.