Green Tracing Dye - Highly Visible Concentrated Fluorescent Leak Detection Dye - 1 Gallon

Easy to see in daylight. Used it to confirm patency of positive crawl space drain.

Just what I ordered

This product proved conclusively that during a heavy rain water flowing under my land from a road catch basin had long ago found a way out of an apparently broken drain pipe and caused a large cave-in on my driveway. Hole is 40 inches wide and 40 inches deep, and also extends an unknown distance under the asphalt that is still intact. My town cannot dispute the results and will remedy the situation and repair my driveway. The photo shows the green dye just arriving in the big hole several minutes after I poured some into the catch basin on the road during a heavy rain.

Worked perfectly for my Halloween display. Color was great.