Although Shinai is made from bamboo which is of strong organic material, after numerous amounts of impacting strikes they could possibly splinter or chip. This can be dangerous if you were to strike your fellow Kendo players which can cause injury, cuts and bleeding. Shinai maintenance is a standard practice and this product is designed to remove any chips or splinters from your shinai to ensure that your equipment meets the correct safety standards to play.
 
Note: Every Kendo player should have this product in their shinai bag. There are 2 sides to the Polishing block the brown side is to remove the splinter or chip and the white side is to polish it down once the defect has been removed.
 
Never use this product on carbon shinai.