Ive been using Rez Block for years. It's a great product but the packaging is highly misleading as per dosage statements. I've always found that you actually need quite a bit more product for it to work as they describe. It also should be refrigerated because it grows mold in the bottle if you dont.
So... it states that this bottle is good for up to 120 uses. Considering a typical drop has the volume of .05ml's and the dosage is 7-14 drops per use, then based on simple mathematics you get a max of 85.7 uses at the prescribed 7ml per use. If you have have a deep water glass piece and use 14drops you max out at 42.8 uses. But as I've stated you need a bit more to obtain stated performance of the product.
In order to obtain the stated 120uses your max dose per use is only 5 drops which wouldnt do anything for cleaning the glass unless you had one of the tiny orb rigs and even that is speculate.
Hmmmmmm... are they purposefully misleading the public on the labeling of their product. You decide for yourself.