Plast-O-Matic Series GYW Wafer Style Double Cylinder Wall Flow Indicators 1 1/2″ – 8″
Plast-O-Matic Series GYW Wafer Style Double Cylinder Wall Flow Indicators 1 1/2" - 8"
https://www.watercareproducts.com.sg/product/sight-glasses-level-indicators-calibration-columns/plast-o-matic-series-gx-gy-gyw-sight-flow-glasses