This has changed my world. Truly.
I've been using this product for a few months and my glassware is perfectly sparkling. I also continue to use the JetDry product in its built-in dispenser--our city water is hard enough to cause issues without requiring a (dreaded) water softener.
(My daughter and niece absolutely refused to shower at GG's house when they were growing up because the water was silky-slimy. Over conditioned...)
Read the Finish product packaging carefully, because the distributor (manufacturer-?) Reckitt Benckiser has made frequent name and labeling changes.
While this is a 16 oz. (453g.) box, it is quite small--approximately 4-1/2"W x 6"H x 1-1/4"D. Think... 4 x 6 index card-sized.
As far as I can tell, you can use any kind of dishwasher powder you like as long as you add 1/4 cup of this to the bottom of your dishwasher before running the load. I said powder, because I've found the gels and tablets don't perform in the same league as the grittier, slightly abrasive dish cleaning powders. Also, skip the brands or versions with a citrus element as that can stain/discolor flatware.
Originally recommended here.