Boker SO4PRO K Titanium Koppo 5 1/8″ overall. Grade 4 titanium shaft. Features double finger loop in the middle of the shaft that allows you to hold the koppo and use your hands without having to put the koppo down and prevents dropping or losing the koppo while using it in a defensive situation. Designed for defensive use, as well as a capable massage tool for relaxation of muscle tightness using the innovative rounded tip