How Elastomeric Valves Helps Improve User Experience in Compact Designs
https://industrialvalvemats.capitaljays.com/posts/why-mini-optics-require-careful-mold-design-and-clean-production
Designing a small part can affect the whole product. A elastomeric valves may look simple, but it has a real job to do. It must work with the cap, case, fluid, air path, or light path around it