AS568-109 O-Ring

Inside diameter 0.299″
Cross-section 0.103″
Outside diameter 0.505″
Metric (ID × CS) 7.59 × 2.62 mm

OD is derived: ID + 2 × CS = 0.299″ + 2 × 0.103″ = 0.505″.

Neighboring sizes (CS 0.103″ series)

Dash ID OD ID mm vs -109
-107 0.206″ 0.412″ 5.23 ID −0.093″
-108 0.237″ 0.443″ 6.02 ID −0.062″
-109 0.299″ 0.505″ 7.59
-110 0.362″ 0.568″ 9.19 ID +0.063″
-111 0.424″ 0.630″ 10.77 ID +0.125″
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.