AS568-009 O-Ring

Inside diameter 0.208″
Cross-section 0.070″
Outside diameter 0.348″
Metric (ID × CS) 5.28 × 1.78 mm

OD is derived: ID + 2 × CS = 0.208″ + 2 × 0.070″ = 0.348″.

Neighboring sizes (CS 0.070″ series)

Dash ID OD ID mm vs -009
-007 0.145″ 0.285″ 3.68 ID −0.063″
-008 0.176″ 0.316″ 4.47 ID −0.032″
-009 0.208″ 0.348″ 5.28
-010 0.239″ 0.379″ 6.07 ID +0.031″
-011 0.301″ 0.441″ 7.65 ID +0.093″
Data provenance. SAE AS568, Aerospace Size Standard for O-rings (SAE International). Nominal dimensions per AS568; size tolerances vary by dash number and are not yet cataloged. Groove/gland design depends on the application — consult a gland design reference. See all data sources.