Perfect Fit Fat Boy Cruiser is made of SilaSkin this product has stretch factor 1200%! SilaSkin is irresistibly soft and safe with all lubes. SilaSkin is a proprietary blend of TPR and Silicone. Category: Fat Boy Line of SilaSkin Products, Cock and Ball Toys, Cock Rings. The super stretchy cock ring that fits any man and is soooo soft! Materials: SilaSkin TPR/Silicone Blend.