A 1/2-inch ID rubber grommet has a nominal internal passage of 12.7 mm. ID describes the opening through the grommet, not the panel cutout.
For mounting fit, use the specified hole dimensions and panel-thickness range. The outside flange normally overlaps the cutout, so its diameter should not simply be used as the required hole size. Check groove geometry and tolerances.
Confirm cable and connector clearance, material compatibility and installation method. An open grommet provides edge protection; sealing and long-term durability depend on the selected profile, compound and service conditions.
