Hayward Universal H200FD Negative Pressure Indoor Vent Adapter (UHXNEGVT12001) kingtechnology a focused replacement like this

a focused replacement like this can be one of the most practical ways to restore the original feel

Raypak stack adapter

this wet end helps restore stronger water handling and supports a cleaner

This item is intended for targeted replacement during troubleshooting or rebuild work

or no longer sealing correctly

Hayward Universal H200FD Negative Pressure Indoor Vent Adapter (UHXNEGVT12001) kingtechnology a focused replacement like thisThe Hayward indoor vent adapter is designed for compatible Universal H200FD heater applications where a negative pressure indoor vent system needs the proper transition fitting. An adapter like this is useful because it helps connect the heater to the venting system in a way that supports a cleaner and more appropriate installation. This replacement is especially useful when the original adapter is damaged, missing, or not suited to the intended vent