There are many inquiries about the shelf life for commercial diaphragms. Our manufacturer, of the original material, states that the shelf life is indefinite as long as the material is kept clean and at a constant, stable temperature. Once the diaphragm is installed in the compass, under harsh weather conditions, exposed to compass fluid and UV light, we warranty them for two years. On average, the compass will not leak for 5-10 years dependent upon the conditions. All of that said, we have placed a 2-year shelf life from the date the material arrives at our customer's dock. Please be advised that we strongly recommend that these diaphragms be installed by FAA licensed overhaul/repair stations only.