Thermoplastic Rubber – Flexible and stretchy this material may be clear or opaquely pigmented and is frequently used for cock rings and flexible strokers or penis pump insert sleeves. Generally Safe for both Silicone and Water Based Lubes, however you should keep this material away from Oil-Based Lubes and massage oils.
Most TPR compounds should be stored separately from PVC products in your toybox as these materials may have a chemical conflict which causes undesirable breakdown of the material.