Intersting. not sure what those cross hairs are made of but did you know during WW2 Black widow silk was used for this? it's stronger than steel (ratio of density), tougher than kevlar, it's also some of the strongest silk of any spider, you can tell the difference if you break up a black widow's web vs most other spiders
You have no idea how many of those things I've killed around my house. I normally don't care if spiders are around. Those and brown recluse spiders get killed though. I'm not talking about squishing them either. They either get burned with a laser or fire.
Usually is a cross made of hairs. These days synthetic thread. My cheap scope that came with my bb gun looks like it has crosshairs stamped out of a sheet of black paper :crackup: