- 4" cast-iron spigot to fit fresh air vent.
- Designed to keep trash and birds from clogging vent stacks
- Top grate measures 4-3/8" across tabs to fit inside a 3-11/16" opening
- Painted Black.
4" cast-iron spigot to fit fresh air vent. Vent fits inside a 4" pipe such as a vent stack, designed to keep trash and birds from clogging the stack. Painted Black. Top grate measures - 4-3/8" across Tabs fit inside a 3-11/16" opening