Some types of spider silk are stronger than Kevlar®, the material used to make bulletproof vests. The Darwin’s bark spider is able to produce silk that is twice the strength of any other spider silk and more than 10 times stronger than Kevlar®. In addition to being tougher than the bulletproof vest material, spider silk is extremely durable and is estimated to be able to withstand stretching to 40% more than its original length without breaking. Spider silk is strong enough and flexible enough that it could be used for a variety of applications, such as space suits or artificial blood vessels.
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