These beautifully designed Ben Wa balls can be used to strengthen the pelvic floor muscles. They provide subtle stimulation, which does not mean that the user will reach immediate orgasm, but rather serves to tease! Hold the balls under running lukewarm or cold water, and the premium borosilicate material warms up or cools down for enhanced temperature play. Weight per ball: 34 grams. Unique design. Use cold or hot water to cool down or heat up. Handmade and made of borosilicate glass. Shatterproof and body-safe.