The S2485-1 is an aircraft fuel cell drain valve used for controlled fuel sampling and drainage from fuel tanks or fuel system sump points. It is designed to allow quick inspection of fuel contamination (water, debris, sediment) during pre-flight and maintenance procedures while maintaining a secure, leak-resistant seal during normal operation.

This part is commonly used in Cessna/Textron aircraft fuel systems and is part of a safety-critical fuel drainage assembly. It is listed as a replacement for legacy fuel drain valve part 127B, which is used in similar fuel system drain applications across older aircraft configurations.

The valve typically operates as a spring-loaded or push-to-open mechanism depending on configuration, allowing fuel samples to be drawn without removing panels or disturbing fuel system integrity.

Key features include:

Aircraft fuel cell drain valve (OEM airframe component)
Replaces legacy valve 127B design
Used for fuel contamination and water checks
Designed for sump, tank, or fuel system drain points
Spring-loaded / push-to-open operation (variant dependent)
Sealed design for leak prevention in flight
Safety-wire provision on many configurations
Corrosion-resistant aviation-grade metal construction
Compatible with Cessna/Textron fuel system installations
Used in routine pre-flight inspection and maintenance procedures
Designed for high reliability in vibration and fuel exposure environments
Traceable OEM/IPC-controlled aircraft part