Figure-eight loop is a type of knot created by a loop on the bight. It is used in climbing and caving.
The double figure eight is used to put a loop in the end of a rope, or around an object. It is relatively easy to tie and is secure, but can become difficult to untie after heavy loading, and can jam badly in any rope type. (sources from wikipedia)
The 3cm*4cm cache is near Huazhong Campground. Please bring your own pen. The log paper has to be signed as Found.