Genuine Deer Sinew Bow Strings. Due to increased popular requests, we are now offering genuine sinew strings to our website for customers. These strings are typically 1/8″ minimum – 3/16″ thick max. These are hand made to fit the approximate length of your bow. The top limb end has a loop twisted into the string. The bottom limb end runs long so you can tie a bowline knot at your desired length. These strings have a 30 day warranty, however, if you take care of them they should last for many years of hard use. These strings do take quite a bit of material, experience, and time to build so they are considerably more expensive than a modern bowstring. That is why I have always encouraged folks to make their own sinew strings using the video linked at the bottom of the page. Since I know everyone doesn’t want to make their own sinew string but still really want to experience a true primitive hunting string, we have you covered!