The COCKSLING is design by OXBALLS. The COCKSLING is the best cock and ball piece that we have ever seen and used! It was designed to hugs every body part in just the right way. The COCKSLING has a divot for your urethra that lets the release of fluids pass easier while the rest fits with amazing contour, with an added ball stretcher. It is very stretchy and can increase to more than double its size, with excellent tear strength. The COCKSLING is not made from the same silicone used in the workshop at OXBALL Studios. The COCKSLING is made from heavy duty TPR (Thermoplastic Rubber) and performs like Vulcanized Rubber. You are going to love this item! Do Not Use Oil Based Lubes with this product.