Silky smooth and weighted for anal play, Crystal glass is also ideal to experiment with temperature play. Crystal Glass is 100% hygienically superior borosilicate glass. Annealed for safety and available is a variety of shapes and sizes. What Annealed means is that the glass is heated in an Annealed Kiln to prevent any fractures or occlusions in the glass, making it tough and strong. As the name says Crystal Clear. Suitable with all lubricants.