Methyltin mercaptide is widely used as a stabilizer in the production of polyvinyl chloride (PVC). It enhances the thermal stability of PVC during processing, preventing degradation and discoloration when exposed to heat. This chemical is particularly effective in rigid PVC applications, such as pipes, fittings, and profiles, where it ensures durability and maintains the material's mechanical properties. Additionally, it is utilized in the manufacturing of transparent PVC products, where clarity and stability are critical. Its compatibility with PVC formulations makes it a valuable component in the plastics industry, contributing to the production of high-quality, long-lasting materials.