The 20" Twist-Lock Ishi stick gives you all the benefits of regular Ishi sticks but has one big advantage. The biggest advantage of the twist lock design is the nail can be adjusted with no tools. The integrated collet allows for adjusting by simply twisting the nose cone, adjusting and retightening. Ishi sticks gives far more power, making it most knappers go to choice for flakers. This Ishi stick is a solid (one piece) model. Boasting a 4" long presharpened copper nail held in with the Twist-Lock collet. This tool is not intended for indirect percussion. We do offer an indirect percussion stick on the website. This Item is discontinued and we have a limited stock.