Note that this is called the Oysterflex bracelet and not a rubber strap. This is because unlike a rubber strap the Oysterflex is far more bracelet-like. It is made up
link of as the name suggests
link flexible metal blades manufactured from a titanium and nickel alloy.
link The blades are over-molded with high-performance black elastomer which is extremely durable. The underside of the bracelet features longitudinal cushions which aid in both comfort and wearability.