The classic evenflo glass vented bottles. The word classic is the best way to describe these bottles. They are a designed like the bottles my mom used when I was a baby. Now and days with all the toxins that are in plastic bottles, I love the fact that they are glass. The bottles are a little heavier then the plastic bottles but, that is to be expected. The silicone pro flow nipple rapidly releases air bubbles into the bottle, not your babies tummy. I love the fact that they one piece nipple and vent means no extra parts to clean or lose. I have tried several different bottles either the nipples are to big, or she has a hard time latching onto the nipple. With this simple design she had no problems at all. They do come with white plastic caps. For more information click here.