249-0873-000 is a plastic protective dust cap designed for MIL-DTL-5015 MS-series circular connectors manufactured by ITT Cannon. The cap is constructed from red polyethylene material and is designed to protect the coupling and conduit ends of MS connectors from foreign matter accumulation and damage to threaded parts. It is compatible with various shell sizes and connector types including MS3100ER, MS102ER, and MSF configurations. The plastic dust caps are reusable and provide cost-effective protection for connectors in storage or during transport, though they are not intended to replace standard aluminum dust caps for permanent installations. These accessories are commonly used in aerospace, military, and commercial applications requiring reliable connector protection.