Value Collection ZMSCFS348 Fluorosilicone O-ring Dash 348

Product Description

The VALUE COLLECTION ZMSCFS348 is a fluorosilicone O-ring with a round cross section, designed for static and dynamic sealing applications that demand reliable performance across extreme temperature ranges and exposure to petroleum-based fluids. It measures 4.375 inches inside diameter, 4.75 inches outside diameter, and 0.1875 inches thick, conforming to the Dash 348 sizing standard. The fluorosilicone compound delivers good resistance to both low and high temperatures as well as strong resistance to petroleum oils and fuels. This O-ring is compliant with MIL-R-25988 Type 1 Class 1, making it suitable for aerospace-grade fuel system sealing and related demanding service environments.

This O-ring sees use in aerospace fuel systems, hydraulic circuits, and any application requiring resistance to diester-base lubricants up to 350 degrees F. It is also appropriate for industrial sealing applications where petroleum oil and fuel contact is a factor. Licensed A and P mechanics, hydraulic system technicians, and industrial maintenance professionals typically source this part for scheduled maintenance, overhaul work, or system repairs. Note that due to limited abrasion resistance, application selection should account for this material characteristic when dynamic contact wear is a concern.

Key Features

• Fluorosilicone compound rated from -80 degrees F to 400 degrees F operating temperature range
• Round cross section conforming to Dash 348 standard dimensions
• MIL-R-25988 Type 1 Class 1 compliant for aerospace and defense applications
• Excellent resistance to petroleum oils and fuels including diester-base lubricants
• Hardness rating of 70 Shore A (Hard) for stable sealing under compression
• Blue color for easy material identification during inspection and installation

Compatibility

Designed as a Dash 348 standard O-ring replacement for aerospace fuel systems, hydraulic systems, and industrial assemblies requiring fluorosilicone sealing material with resistance to petroleum products and diester-base lubricants.

Installation Notes

Installation should be performed by qualified mechanics or technicians familiar with sealing system procedures. Depressurize and drain the system fully before removing the old O-ring and inspect the groove for damage, burrs, or contamination before seating the new ring. Lubricate the O-ring with a fluid compatible with fluorosilicone prior to installation to prevent twisting or tearing during assembly. Do not use petroleum-based greases incompatible with fluorosilicone compounds, and do not overstretch the ring during fitting.