Macherey-Nagel, 90725, Dipyridyl Paper, Box of 200 Strips

My team and I used these a bunch for wetland delineations when I worked in California. We kept the container with the strips in the refrigerator at work, taped shut, with a note for ownership so our admin staff wouldn't throw them out during fridge purges. The strips did not work well until we started damping them with cheap white vinegar after we laid the strips along the soil profile to facilitate the reaction. A small sample bottle filled with white vinegar became part of our wetland delineation kits.

Must first spray with vinegar for them to work

Order arrived faster than expected. Test paper is easy to use and much more convenient than liquid AAD for field work. Test paper comes in a convenient plastic box.