The ripple effect on our lakes and rivers inspired this new design, Cantel Blown Glass Artisans explain. They craft the tumblers by hand, using traditional blown glass techniques featuring waves in orange, yellow, green, blue and lilac. Because each piece is handmade, shape and size can vary slightly and tiny bubbles may appear within the glass. This exemplifies the hand-blown technique, making every piece a unique example of blown glass craftsmanship.