They are designed specifically for cleaning the fibre end-faces or connectors in order to maximize the performance of light transport. They remove any dust, oil and pollutants leaving no residue on the fibre. Using these towels it is unnecessary to transport liquid alcohol, which can always be dangerous.
A key feature is these towels are 100% free of water; the water is an element to avoid while cleaning fibre optics. Towels come in sealed bags, so they can withstand the test of time until they are used. They leave no lint.
They contain the exact amount of alcohol: do not leak or expel an excess of steam.