Which of the following is NOT one of the single point anchor systems?

The double bowline is not considered a single point anchor system, making it the correct choice in this context. Single point anchor systems are primarily designed for securing a load to a single point, ensuring that the anchor is stable and can efficiently transfer forces. They simplify the setup and help to maintain control over the load.

The wrap-3, pull-2 system is a technique that provides a strong anchor using a wrap around an object, effectively distributing forces. The tensionless hitch is another method that creates a secure anchor without putting excessive force on the anchor point, making it ideal for maintaining the integrity of the attachment point. The figure eight follow through is a knot used to create a secure loop that can serve as part of an anchor system.

In contrast, the double bowline is primarily used for creating a loop in the end of a rope rather than functioning as a standalone anchor system. While useful in various applications, it does not share the primary characteristics that define single point anchor systems.