The strongest silicone cups on the market. The Siliskin® "Super" 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. Warm up drinks in the Siliskin Super Cup. The perfect alternative to plastic cups. Great for on the go, indoor, outdoor, boating, camping, poolside and everyday use.