Anarchism is a philosophy that embodies many diverse attitudes, tendencies and schools of thought; as such, disagreement over questions of values, ideology and tactics is common. The compatibility of capitalism, nationalism, and religion with anarchism is widely disputed.
I should have been more clear. The systems where I typically see Teflon used are water systems (either automotive or household plumbing) and pneumatic systems where the tape is used on a tapered male thread. In those cases, the male thread could be tightened without the Teflon tape, in many cases without leaks.
Powdered aluminium pigment gives traditional duct tape its silvery grey colour. Duct tape, sometimes called duck tape, is cloth- or scrim-backed pressure-sensitive tape, often coated with polyethylene. There are a variety of constructions using different backings and adhesives. One variation is black gaffer tape, which is designed to be non-reflective and cleanly removed, unlike standard duct tape.