Akcrostab™ T-5311P is a stateoftheart organotin, reverse ester mercaptide, heat stabilizer containing 8.5% tin. It is designed for use prmiarily in large diameter pipe and is pending NSF approval. Akcrostab™ T-5311P exhibits the same color development profile and thermal stability, on an equal phr basis, as the leading substrate stabilizer. The suggested usage level is 0.7 to 1.5 phr depending on the heat stability required. Akcrostab™ T-5311 has been designed to contain a mercaptan chemical trap. This results in a uniquely low odor product, both in the neat stabilizer and during the extrusion process.