1/4" Anti-vacuum Valve
There are many names for this part, but a brief description should suffice: this valve allows air to escape the boiler as the water heats up, hissing and then closing off when the boiler water reaches its operating temperature, sealed by the steam pressure created. This will replace the other version no problem. A gasket is recommended for this version, however.
Complete only; no internal parts are available for this item.
My old valve was leaking water, this new one is working fine.