Replacement sight glass for G1'' flow indicator

Replaces the Pyrex glass window of the 1" brass impeller flow indicator. A scratched, dirty or broken glass can be changed without replacing the indicator body, which saves the cost of a new indicator. The glass has the same limits as the indicator: water and mild water-based liquids up to +90 °C (≈194 °F). Choose the glass that matches the thread size of the installed indicator.