Used as a stabilizer in polyvinyl chloride (PVC) plastics to prevent degradation during processing and exposure to heat and light. It helps maintain the color and structural integrity of PVC products, especially in rigid applications like pipes, window profiles, and sheets. Also acts as a catalyst in certain polymerization reactions and may be used in specialty coatings where thermal stability is required. Its application is limited due to environmental and toxicity concerns associated with organotin compounds.