Confirm the unit and reference dimension for a 2-1/2 rubber grommet. If the unit is inches, the measurement is 63.5 mm; it may describe a mounting hole, passage or other feature.
Check panel thickness, groove geometry, flange clearance and cable dimensions. Select the compound for the actual temperature and substances encountered in service.
Rubber families differ in resistance to weather, acids, alkalis and mechanical wear. NBR (Nitrile) is one rubber family. Use grade-specific data and verify the part in the intended assembly.
