US Seal Shaft Seal [PS 3870 3 4" Viton] (PS 3870) aquasol this fastening kit helps restore this fastening kit helps restore dependable blanket attachment and contributes to better overall cover reel operation A properly selected replacement helps preserve the intended fit and serviceability of the assembly instead of forcing a substitute that only partly aligns with the application Helps protect pump motors from water migration through the shaft area The US Seal Shaft Seal [PS 3870 3 4" Viton] is a replacement pump shaft seal from US Seal Manufacturing designed to help prevent water from leaking along the pump shaft in compatible pool and spa pump assemblies