Thank for the question With respect to your specific product, we do not have enough information in order to guide you in your design phase, however, we can provide some guidelines to help you achieve your desired outcome. Silicone comes in different states and depending upon how you want to process the material and what your final manufacturing process is will determine what raw state you will be working with. For any type of pouring or injection molding you will be looking at the liquid silicone rubber (LSR) series, whereas, if you are looking to produce silicone parts from compression molds, you will need to consider the semi-solid state silicones. With your product (a cylinder), you would more than likely be considering the LSR series as a cylinder would be produced in a mold. Silicone as a raw material will have additives mixed in to alter the physical properties and how the final molded part behaves from a mechanical point of view. Remember, some silicone products are hard, the solid tires of a forklift truck for example, on the other end of the spectrum, a rubber band is soft and very flexible with a very high elongation ratio, much more than the 180% we talk about in the presentation. For your cylinder product, you need to ensure you select the correct silicone with a low Durometer Shore hardness value, maybe on the 00 scale, this will ensure your inflatable cylinder is able to expand and contract without bursting. You also need to consider the two dimensions, not inflated and fully inflated, you can then calculate the elongation or expansion requirements, from there you will be able to determine what the other mechanical properties would be, such as the tensile strength, which should give you a guide to the silicone grade that will be suitable for your product design. Always remember to build in a factor of safety when designing products. We hope this helps guide you in your product design.