Genuine Merrill H-41 brass plunger. This plunger comes with the seals to stop leaks out of the spout on the Merrill H3000 Heated Hydrant. Before installing a new plunger it is highly recommended to use hydrant, or faucet grease to lubricate the plunger, and the connected O-rings. The lubrication will help insure smooth operation of the hydrant.