i-blythe S5050 is Cuprous Iodide. Acts as a heat and light stabilizer & used to counteract the destructive effects of heat and light on polyamides in conjunction with Potassium Iodide. It prevents discoloration and preserves mechanical properties of Nylon 6 and Nylon 66. It contains no impurities.
blythe S5071 by William Blythe is potassium iodide. In combination with copper salts, it acts as a heat / light stabilizer to protect polyamides against degradation by heat and light.