Used to determine the level of SO2 in your wine. Contains 10 tests in the form of glass titrets. They can be used by themselves or you can purchase W510B which is a titret holder. Please keep in mind that due to some chemical interference, this kit is only accurate to within +/- 30ppm when used to test red wines.
We started using Titrets for measuring SO2 levels in white wine. It is a nice and easy to use instrument, but two negative comments: a) It is impossible to use without titrettor. b) Instructions are not clear enough. Total lack of pictures. We managed to use titrets thanks to instructions available in YOUTUBE. Also learned a lot of other interesting stuff available from titrets people.
I use Titrets to test for S02 levels in white wine. It always reads a little high, maybe 10-15% but you can correct for that error. I find it easy, inexpensive and I have never had a white wine develop bacteria problems when using Titrets to test for S02.
Red wines are considerably more difficult to test with Titrets unless it is very light in color as color change is critical for accurate reading. I don't use the product for red wines.