Don't get the 35% on the rubber part of the dropper. It will destroy it rather quickly. The only problem with glass and H2O2 (Hydrogen-Peroxid) is the fact that if a gallon of 35% is stored in glass at room temp tightly sealed, the off-gassing of the nascent oxygen can cause enough pressure in the container to burst it. Refrigeration of the H2O2 (Hydrogen-Peroxid) will stop this from happening and preserve the potency of the H2O2. You can even put it in the freezer. 35% will not freeze. Otherwise, glass is a preferable container for H2O2 (Hydrogen-Peroxid) because it is inert and non-reactive with the H2O2.