The dart rest is made of two pieces of rawhide or one big piece doubled over and held together with a wrapping of string or sinew part way to the ends. The dart is slip into between the two unwrapped ends which grip the dart just enough to hold it in place but not tight enough to prevent its release during the throwing motion. These atlatls are attributed to “Mike” but his last name is not given on the web site. Hell, Mike could be the dog. I left a comment on the web page with my email address. Hope I get a response.