I am constantly scoping out bottles at the supermarket to see which ones would work best for sensory bottles. I found these Voss water bottles at Marketstreet and even though they were pricey at $1.69 a bottle, I think it was worth it. They did not have a ton of adhesive to remove and they were sleek. I think for toddlers Aquapod bottles still work best for their chubby hands, but these are awesome for more advanced children. This bottle is filled 2/3 way with Karo syrup, red beads, and topped with water with a few drops of red food color.