A closed rubber grommet plug covers an unused panel opening. Its retaining profile must fit the hole and panel thickness so that it stays seated in the intended assembly.
Identify the size
A description such as 1/2 inch is incomplete unless the drawing identifies the dimension. One half inch equals 12.7 mm, but the mounting-hole diameter, flange outside diameter and overall depth still need to be checked separately.
Covering versus sealing
A plug can cover an opening without providing a verified liquid or pressure seal. Specify the required ingress protection or pressure conditions and confirm the part and assembly evidence where applicable.
Select material for the temperature and actual fluids. Before ordering, record the drawing reference, panel dimensions, compound and quantity. Inspect the fitted plug for secure seating and damage.
