Panduit DTHH-Q0 Dura-Ty Cable Tie Heads are weather, chemical, and UV-resistant for harsh outdoor power and communications applications. The durable locking mechanism, complete with double stainless steel locking barbs, provides a consistent, reliable connection and high-impact resistance and strength. Heavy cross section, are made of Weather Resistant Acetal. They are black in color and come in packages of 25.