The Siliskin® Silicone Cups are 100% silicone with an embedded stainless steel ring to hold it's shape. It won't collapse when gripped. It's also MICROWAVE SAFE. That's right! Our patented technology paves the way for a new drinking experience. Warm up drinks in the Siliskin Super Cup. The perfect alternative to plastic cups! Great for on the go, indoor, outdoor, boating, camping, rving, poolside and everyday use! GoSili!