AS568-370 O-Ring

Inside diameter 8.225″
Cross-section 0.210″
Outside diameter 8.645″
Metric (ID × CS) 208.91 × 5.33 mm

OD is derived: ID + 2 × CS = 8.225″ + 2 × 0.210″ = 8.645″.

Neighboring sizes (CS 0.210″ series)

Dash ID OD ID mm vs -370
-368 7.725″ 8.145″ 196.21 ID −0.500″
-369 7.975″ 8.395″ 202.56 ID −0.250″
-370 8.225″ 8.645″ 208.91
-371 8.475″ 8.895″ 215.26 ID +0.250″
-372 8.725″ 9.145″ 221.61 ID +0.500″
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.