Ordered as V1.78X8.73, this is a black Viton® (FKM) 75 Shore A O-Ring with an inside diameter of 8.73 mm (0.344 in), a cross section of 1.78 mm (0.07 in), and an outside diameter of 12.29 mm (0.48 in). The o-ring seats in a machined groove and forms a leak-tight barrier when compressed between two mating surfaces.
The material holds up against aggressive chemicals, many acids, and aromatic hydrocarbons. That behavior comes from the compound itself: Viton® (FKM) offers the industry benchmark where nitrile reaches its thermal limit, excellent resistance to compression set and permeation. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in ketones and esters or low-molecular-weight organic acids.
Maintenance and OEM teams specify it across automotive fuel systems, aerospace, and oil and gas.
Order part number V1.78X8.73, sold individually. Application requirements vary, so validate compatibility with your process conditions prior to installation.
description 1.78MM CS X 8.73MM ID BLACK FKM 75D
uf_description2 METRIC O-RING
Actual_OD 12.29 mm (0.48 inch)
Actual_CS 1.78 mm (0.07 inch)
Actual_ID 8.73 mm (0.344 inch)
ProductCode Description O-Rings - Metric - Commodity